src/network/networkd-neighbor.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include "sd-netlink.h"
   4
   5 #include "alloc-util.h"
   6 #include "conf-parser.h"
   7 #include "ether-addr-util.h"
   8 #include "hashmap.h"
   9 #include "in-addr-util.h"
  10 #include "netlink-util.h"
  11 #include "networkd-link.h"
  12 #include "networkd-manager.h"
  13 #include "networkd-neighbor.h"
  14 #include "set.h"
  15
  16 void neighbor_free(Neighbor *neighbor) {
  17         if (!neighbor)
  18                 return;
  19
  20         if (neighbor->network) {
  21                 LIST_REMOVE(neighbors, neighbor->network->neighbors, neighbor);
  22                 assert(neighbor->network->n_neighbors > 0);
  23                 neighbor->network->n_neighbors--;
  24
  25                 if (neighbor->section)
  26                         hashmap_remove(neighbor->network->neighbors_by_section, neighbor->section);
  27         }
  28
  29         network_config_section_free(neighbor->section);
  30
  31         if (neighbor->link) {
  32                 set_remove(neighbor->link->neighbors, neighbor);
  33                 set_remove(neighbor->link->neighbors_foreign, neighbor);
  34         }
  35
  36         free(neighbor);
  37 }
  38
  39 static int neighbor_new_static(Network *network, const char *filename, unsigned section_line, Neighbor **ret) {
  40         _cleanup_(network_config_section_freep) NetworkConfigSection *n = NULL;
  41         _cleanup_(neighbor_freep) Neighbor *neighbor = NULL;
  42         int r;
  43
  44         assert(network);
  45         assert(ret);
  46         assert(!!filename == (section_line > 0));
  47
  48         if (filename) {
  49                 r = network_config_section_new(filename, section_line, &n);
  50                 if (r < 0)
  51                         return r;
  52
  53                 neighbor = hashmap_get(network->neighbors_by_section, n);
  54                 if (neighbor) {
  55                         *ret = TAKE_PTR(neighbor);
  56
  57                         return 0;
  58                 }
  59         }
  60
  61         neighbor = new(Neighbor, 1);
  62         if (!neighbor)
  63                 return -ENOMEM;
  64
  65         *neighbor = (Neighbor) {
  66                 .network = network,
  67                 .family = AF_UNSPEC,
  68         };
  69
  70         LIST_APPEND(neighbors, network->neighbors, neighbor);
  71         network->n_neighbors++;
  72
  73         if (filename) {
  74                 neighbor->section = TAKE_PTR(n);
  75
  76                 r = hashmap_ensure_allocated(&network->neighbors_by_section, &network_config_hash_ops);
  77                 if (r < 0)
  78                         return r;
  79
  80                 r = hashmap_put(network->neighbors_by_section, neighbor->section, neighbor);
  81                 if (r < 0)
  82                         return r;
  83         }
  84
  85         *ret = TAKE_PTR(neighbor);
  86
  87         return 0;
  88 }
  89
  90 static int neighbor_configure_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
  91         int r;
  92
  93         assert(m);
  94         assert(link);
  95         assert(link->neighbor_messages > 0);
  96
  97         link->neighbor_messages--;
  98
  99         if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
 100                 return 1;
 101
 102         r = sd_netlink_message_get_errno(m);
 103         if (r < 0 && r != -EEXIST)
 104                 /* Neighbor may not exist yet. So, do not enter failed state here. */
 105                 log_link_warning_errno(link, r, "Could not set neighbor, ignoring: %m");
 106
 107         if (link->neighbor_messages == 0) {
 108                 log_link_debug(link, "Neighbors set");
 109                 link->neighbors_configured = true;
 110                 link_check_ready(link);
 111         }
 112
 113         return 1;
 114 }
 115
 116 int neighbor_configure(Neighbor *neighbor, Link *link, link_netlink_message_handler_t callback) {
 117         _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
 118         int r;
 119
 120         assert(neighbor);
 121         assert(link);
 122         assert(link->ifindex > 0);
 123         assert(link->manager);
 124         assert(link->manager->rtnl);
 125
 126         r = sd_rtnl_message_new_neigh(link->manager->rtnl, &req, RTM_NEWNEIGH,
 127                                           link->ifindex, neighbor->family);
 128         if (r < 0)
 129                 return log_error_errno(r, "Could not allocate RTM_NEWNEIGH message: %m");
 130
 131         r = sd_rtnl_message_neigh_set_state(req, NUD_PERMANENT);
 132         if (r < 0)
 133                 return log_error_errno(r, "Could not set state: %m");
 134
 135         r = sd_netlink_message_set_flags(req, NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE);
 136         if (r < 0)
 137                 return log_error_errno(r, "Could not set flags: %m");
 138
 139         r = sd_netlink_message_append_data(req, NDA_LLADDR, &neighbor->lladdr, neighbor->lladdr_size);
 140         if (r < 0)
 141                 return log_error_errno(r, "Could not append NDA_LLADDR attribute: %m");
 142
 143         r = netlink_message_append_in_addr_union(req, NDA_DST, neighbor->family, &neighbor->in_addr);
 144         if (r < 0)
 145                 return log_error_errno(r, "Could not append NDA_DST attribute: %m");
 146
 147         r = netlink_call_async(link->manager->rtnl, NULL, req, callback ?: neighbor_configure_handler,
 148                                link_netlink_destroy_callback, link);
 149         if (r < 0)
 150                 return log_error_errno(r, "Could not send rtnetlink message: %m");
 151
 152         link->neighbor_messages++;
 153         link_ref(link);
 154
 155         r = neighbor_add(link, neighbor->family, &neighbor->in_addr, &neighbor->lladdr, neighbor->lladdr_size, NULL);
 156         if (r < 0)
 157                 return log_link_error_errno(link, r, "Could not add neighbor: %m");
 158
 159         return 0;
 160 }
 161
 162 static int neighbor_remove_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
 163         int r;
 164
 165         assert(m);
 166         assert(link);
 167
 168         if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
 169                 return 1;
 170
 171         r = sd_netlink_message_get_errno(m);
 172         if (r < 0 && r != -ESRCH)
 173                 /* Neighbor may not exist because it already got deleted, ignore that. */
 174                 log_link_warning_errno(link, r, "Could not remove neighbor: %m");
 175
 176         return 1;
 177 }
 178
 179 int neighbor_remove(Neighbor *neighbor, Link *link, link_netlink_message_handler_t callback) {
 180         _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
 181         int r;
 182
 183         assert(neighbor);
 184         assert(link);
 185         assert(link->ifindex > 0);
 186         assert(link->manager);
 187         assert(link->manager->rtnl);
 188
 189         r = sd_rtnl_message_new_neigh(link->manager->rtnl, &req, RTM_DELNEIGH,
 190                                           link->ifindex, neighbor->family);
 191         if (r < 0)
 192                 return log_error_errno(r, "Could not allocate RTM_DELNEIGH message: %m");
 193
 194         r = netlink_message_append_in_addr_union(req, NDA_DST, neighbor->family, &neighbor->in_addr);
 195         if (r < 0)
 196                 return log_error_errno(r, "Could not append NDA_DST attribute: %m");
 197
 198         r = netlink_call_async(link->manager->rtnl, NULL, req, callback ?: neighbor_remove_handler,
 199                                link_netlink_destroy_callback, link);
 200         if (r < 0)
 201                 return log_error_errno(r, "Could not send rtnetlink message: %m");
 202
 203         link_ref(link);
 204
 205         return 0;
 206 }
 207
 208 static void neighbor_hash_func(const Neighbor *neighbor, struct siphash *state) {
 209         assert(neighbor);
 210
 211         siphash24_compress(&neighbor->family, sizeof(neighbor->family), state);
 212
 213         switch (neighbor->family) {
 214         case AF_INET:
 215         case AF_INET6:
 216                 /* Equality of neighbors are given by the pair (addr,lladdr) */
 217                 siphash24_compress(&neighbor->in_addr, FAMILY_ADDRESS_SIZE(neighbor->family), state);
 218                 siphash24_compress(&neighbor->lladdr, neighbor->lladdr_size, state);
 219                 break;
 220         default:
 221                 /* treat any other address family as AF_UNSPEC */
 222                 break;
 223         }
 224 }
 225
 226 static int neighbor_compare_func(const Neighbor *a, const Neighbor *b) {
 227         int r;
 228
 229         r = CMP(a->family, b->family);
 230         if (r != 0)
 231                 return r;
 232
 233         r = CMP(a->lladdr_size, b->lladdr_size);
 234         if (r != 0)
 235                 return r;
 236
 237         switch (a->family) {
 238         case AF_INET:
 239         case AF_INET6:
 240                 r = memcmp(&a->in_addr, &b->in_addr, FAMILY_ADDRESS_SIZE(a->family));
 241                 if (r != 0)
 242                         return r;
 243         }
 244
 245         return memcmp(&a->lladdr, &b->lladdr, a->lladdr_size);
 246 }
 247
 248 DEFINE_PRIVATE_HASH_OPS(neighbor_hash_ops, Neighbor, neighbor_hash_func, neighbor_compare_func);
 249
 250 int neighbor_get(Link *link, int family, const union in_addr_union *addr, const union lladdr_union *lladdr, size_t lladdr_size, Neighbor **ret) {
 251         Neighbor neighbor, *existing;
 252
 253         assert(link);
 254         assert(addr);
 255         assert(lladdr);
 256
 257         neighbor = (Neighbor) {
 258                 .family = family,
 259                 .in_addr = *addr,
 260                 .lladdr = *lladdr,
 261                 .lladdr_size = lladdr_size,
 262         };
 263
 264         existing = set_get(link->neighbors, &neighbor);
 265         if (existing) {
 266                 if (ret)
 267                         *ret = existing;
 268                 return 1;
 269         }
 270
 271         existing = set_get(link->neighbors_foreign, &neighbor);
 272         if (existing) {
 273                 if (ret)
 274                         *ret = existing;
 275                 return 0;
 276         }
 277
 278         return -ENOENT;
 279 }
 280
 281 static int neighbor_add_internal(Link *link, Set **neighbors, int family, const union in_addr_union *addr, const union lladdr_union *lladdr, size_t lladdr_size, Neighbor **ret) {
 282         _cleanup_(neighbor_freep) Neighbor *neighbor = NULL;
 283         int r;
 284
 285         assert(link);
 286         assert(neighbors);
 287         assert(addr);
 288         assert(lladdr);
 289
 290         neighbor = new(Neighbor, 1);
 291         if (!neighbor)
 292                 return -ENOMEM;
 293
 294         *neighbor = (Neighbor) {
 295                 .family = family,
 296                 .in_addr = *addr,
 297                 .lladdr = *lladdr,
 298                 .lladdr_size = lladdr_size,
 299         };
 300
 301         r = set_ensure_allocated(neighbors, &neighbor_hash_ops);
 302         if (r < 0)
 303                 return r;
 304
 305         r = set_put(*neighbors, neighbor);
 306         if (r < 0)
 307                 return r;
 308         if (r == 0)
 309                 return -EEXIST;
 310
 311         neighbor->link = link;
 312
 313         if (ret)
 314                 *ret = neighbor;
 315
 316         neighbor = NULL;
 317
 318         return 0;
 319 }
 320
 321 int neighbor_add(Link *link, int family, const union in_addr_union *addr, const union lladdr_union *lladdr, size_t lladdr_size, Neighbor **ret) {
 322         Neighbor *neighbor;
 323         int r;
 324
 325         r = neighbor_get(link, family, addr, lladdr, lladdr_size, &neighbor);
 326         if (r == -ENOENT) {
 327                 /* Neighbor doesn't exist, make a new one */
 328                 r = neighbor_add_internal(link, &link->neighbors, family, addr, lladdr, lladdr_size, &neighbor);
 329                 if (r < 0)
 330                         return r;
 331         } else if (r == 0) {
 332                 /* Neighbor is foreign, claim it as recognized */
 333                 r = set_ensure_allocated(&link->neighbors, &neighbor_hash_ops);
 334                 if (r < 0)
 335                         return r;
 336
 337                 r = set_put(link->neighbors, neighbor);
 338                 if (r < 0)
 339                         return r;
 340
 341                 set_remove(link->neighbors_foreign, neighbor);
 342         } else if (r == 1) {
 343                 /* Neighbor already exists */
 344         } else
 345                 return r;
 346
 347         if (ret)
 348                 *ret = neighbor;
 349         return 0;
 350 }
 351
 352 int neighbor_add_foreign(Link *link, int family, const union in_addr_union *addr, const union lladdr_union *lladdr, size_t lladdr_size, Neighbor **ret) {
 353         return neighbor_add_internal(link, &link->neighbors_foreign, family, addr, lladdr, lladdr_size, ret);
 354 }
 355
 356 bool neighbor_equal(const Neighbor *n1, const Neighbor *n2) {
 357         if (n1 == n2)
 358                 return true;
 359
 360         if (!n1 || !n2)
 361                 return false;
 362
 363         return neighbor_compare_func(n1, n2) == 0;
 364 }
 365
 366 int neighbor_section_verify(Neighbor *neighbor) {
 367         if (section_is_invalid(neighbor->section))
 368                 return -EINVAL;
 369
 370         if (neighbor->family == AF_UNSPEC)
 371                 return log_warning_errno(SYNTHETIC_ERRNO(EINVAL),
 372                                          "%s: Neighbor section without Address= configured. "
 373                                          "Ignoring [Neighbor] section from line %u.",
 374                                          neighbor->section->filename, neighbor->section->line);
 375
 376         if (neighbor->lladdr_size == 0)
 377                 return log_warning_errno(SYNTHETIC_ERRNO(EINVAL),
 378                                          "%s: Neighbor section without LinkLayerAddress= configured. "
 379                                          "Ignoring [Neighbor] section from line %u.",
 380                                          neighbor->section->filename, neighbor->section->line);
 381
 382         return 0;
 383 }
 384
 385 int config_parse_neighbor_address(
 386                 const char *unit,
 387                 const char *filename,
 388                 unsigned line,
 389                 const char *section,
 390                 unsigned section_line,
 391                 const char *lvalue,
 392                 int ltype,
 393                 const char *rvalue,
 394                 void *data,
 395                 void *userdata) {
 396
 397         Network *network = userdata;
 398         _cleanup_(neighbor_free_or_set_invalidp) Neighbor *n = NULL;
 399         int r;
 400
 401         assert(filename);
 402         assert(section);
 403         assert(lvalue);
 404         assert(rvalue);
 405         assert(data);
 406
 407         r = neighbor_new_static(network, filename, section_line, &n);
 408         if (r < 0)
 409                 return r;
 410
 411         r = in_addr_from_string_auto(rvalue, &n->family, &n->in_addr);
 412         if (r < 0) {
 413                 log_syntax(unit, LOG_ERR, filename, line, r, "Neighbor Address is invalid, ignoring assignment: %s", rvalue);
 414                 return 0;
 415         }
 416
 417         TAKE_PTR(n);
 418
 419         return 0;
 420 }
 421
 422 int config_parse_neighbor_lladdr(
 423                 const char *unit,
 424                 const char *filename,
 425                 unsigned line,
 426                 const char *section,
 427                 unsigned section_line,
 428                 const char *lvalue,
 429                 int ltype,
 430                 const char *rvalue,
 431                 void *data,
 432                 void *userdata) {
 433
 434         Network *network = userdata;
 435         _cleanup_(neighbor_free_or_set_invalidp) Neighbor *n = NULL;
 436         int family, r;
 437
 438         assert(filename);
 439         assert(section);
 440         assert(lvalue);
 441         assert(rvalue);
 442         assert(data);
 443
 444         r = neighbor_new_static(network, filename, section_line, &n);
 445         if (r < 0)
 446                 return r;
 447
 448         r = ether_addr_from_string(rvalue, &n->lladdr.mac);
 449         if (r >= 0)
 450                 n->lladdr_size = sizeof(n->lladdr.mac);
 451         else {
 452                 r = in_addr_from_string_auto(rvalue, &family, &n->lladdr.ip);
 453                 if (r < 0) {
 454                         log_syntax(unit, LOG_ERR, filename, line, r,
 455                                    "Neighbor LinkLayerAddress= is invalid, ignoring assignment: %s",
 456                                    rvalue);
 457                         return 0;
 458                 }
 459                 n->lladdr_size = family == AF_INET ? sizeof(n->lladdr.ip.in) : sizeof(n->lladdr.ip.in6);
 460         }
 461
 462         TAKE_PTR(n);
 463
 464         return 0;
 465 }
 466
 467 int config_parse_neighbor_hwaddr(
 468                 const char *unit,
 469                 const char *filename,
 470                 unsigned line,
 471                 const char *section,
 472                 unsigned section_line,
 473                 const char *lvalue,
 474                 int ltype,
 475                 const char *rvalue,
 476                 void *data,
 477                 void *userdata) {
 478
 479         Network *network = userdata;
 480         _cleanup_(neighbor_free_or_set_invalidp) Neighbor *n = NULL;
 481         int r;
 482
 483         assert(filename);
 484         assert(section);
 485         assert(lvalue);
 486         assert(rvalue);
 487         assert(data);
 488
 489         r = neighbor_new_static(network, filename, section_line, &n);
 490         if (r < 0)
 491                 return r;
 492
 493         r = ether_addr_from_string(rvalue, &n->lladdr.mac);
 494         if (r < 0) {
 495                 log_syntax(unit, LOG_ERR, filename, line, r,
 496                            "Neighbor MACAddress= is invalid, ignoring assignment: %s", rvalue);
 497                 return 0;
 498         }
 499
 500         n->lladdr_size = sizeof(n->lladdr.mac);
 501         TAKE_PTR(n);
 502
 503         return 0;
 504 }