src/network/networkd-link.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2013 Tom Gundersen <teg@jklm.no>
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <netinet/ether.h>
  23 #include <linux/if.h>
  24
  25 #include "networkd.h"
  26 #include "libudev-private.h"
  27 #include "util.h"
  28 #include "bus-util.h"
  29
  30 int link_new(Manager *manager, struct udev_device *device, Link **ret) {
  31         _cleanup_link_free_ Link *link = NULL;
  32         const char *mac;
  33         struct ether_addr *mac_addr;
  34         const char *ifname;
  35         int r;
  36
  37         assert(device);
  38         assert(ret);
  39
  40         link = new0(Link, 1);
  41         if (!link)
  42                 return -ENOMEM;
  43
  44         link->manager = manager;
  45         link->state = _LINK_STATE_INVALID;
  46
  47         link->ifindex = udev_device_get_ifindex(device);
  48         if (link->ifindex <= 0)
  49                 return -EINVAL;
  50
  51         mac = udev_device_get_sysattr_value(device, "address");
  52         if (mac) {
  53                 mac_addr = ether_aton(mac);
  54                 if (mac_addr)
  55                         memcpy(&link->mac, mac_addr, sizeof(struct ether_addr));
  56         }
  57
  58         ifname = udev_device_get_sysname(device);
  59         link->ifname = strdup(ifname);
  60
  61         r = hashmap_put(manager->links, &link->ifindex, link);
  62         if (r < 0)
  63                 return r;
  64
  65         *ret = link;
  66         link = NULL;
  67
  68         return 0;
  69 }
  70
  71 void link_free(Link *link) {
  72         if (!link)
  73                 return;
  74
  75         assert(link->manager);
  76
  77         if (link->dhcp)
  78                 sd_dhcp_client_free(link->dhcp);
  79
  80         route_free(link->dhcp_route);
  81         link->dhcp_route = NULL;
  82
  83         address_free(link->dhcp_address);
  84         link->dhcp_address = NULL;
  85
  86         hashmap_remove(link->manager->links, &link->ifindex);
  87
  88         free(link->ifname);
  89
  90         free(link);
  91 }
  92
  93 int link_add(Manager *m, struct udev_device *device, Link **ret) {
  94         Link *link;
  95         Network *network;
  96         int r;
  97         uint64_t ifindex;
  98         NetdevKind kind;
  99
 100         assert(m);
 101         assert(device);
 102
 103         ifindex = udev_device_get_ifindex(device);
 104         link = hashmap_get(m->links, &ifindex);
 105         if (link) {
 106                 *ret = link;
 107                 return -EEXIST;
 108         }
 109
 110         r = link_new(m, device, &link);
 111         if (r < 0)
 112                 return r;
 113
 114         *ret = link;
 115
 116         kind = netdev_kind_from_string(udev_device_get_devtype(device));
 117         if (kind != _NETDEV_KIND_INVALID) {
 118                 r = netdev_set_link(m, kind, link);
 119                 if (r < 0 && r != -ENOENT)
 120                         return r;
 121         }
 122
 123         r = network_get(m, device, &network);
 124         if (r < 0)
 125                 return r == -ENOENT ? 0 : r;
 126
 127         r = network_apply(m, network, link);
 128         if (r < 0)
 129                 return r;
 130
 131         return 0;
 132 }
 133
 134 static int link_enter_configured(Link *link) {
 135         assert(link);
 136         assert(link->state == LINK_STATE_SETTING_ROUTES);
 137
 138         log_info_link(link, "link configured");
 139
 140         link->state = LINK_STATE_CONFIGURED;
 141
 142         return 0;
 143 }
 144
 145 static void link_enter_failed(Link *link) {
 146         assert(link);
 147
 148         log_warning_link(link, "failed");
 149
 150         link->state = LINK_STATE_FAILED;
 151 }
 152
 153 static int route_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 154         Link *link = userdata;
 155         int r;
 156
 157         assert(link->route_messages > 0);
 158         assert(link->state == LINK_STATE_SETTING_ADDRESSES ||
 159                link->state == LINK_STATE_SETTING_ROUTES ||
 160                link->state == LINK_STATE_FAILED);
 161
 162         link->route_messages --;
 163
 164         if (link->state == LINK_STATE_FAILED)
 165                 return 1;
 166
 167         r = sd_rtnl_message_get_errno(m);
 168         if (r < 0 && r != -EEXIST)
 169                 log_struct_link(LOG_WARNING, link,
 170                                 "MESSAGE=%s: could not set route: %s",
 171                                 link->ifname, strerror(-r),
 172                                 "ERRNO=%d", -r,
 173                                 NULL);
 174
 175         /* we might have received an old reply after moving back to SETTING_ADDRESSES,
 176          * ignore it */
 177         if (link->route_messages == 0 && link->state == LINK_STATE_SETTING_ROUTES) {
 178                 log_debug_link(link, "routes set");
 179                 link_enter_configured(link);
 180         }
 181
 182         return 1;
 183 }
 184
 185 static int link_enter_set_routes(Link *link) {
 186         Route *route;
 187         int r;
 188
 189         assert(link);
 190         assert(link->network);
 191         assert(link->state == LINK_STATE_SETTING_ADDRESSES);
 192
 193         link->state = LINK_STATE_SETTING_ROUTES;
 194
 195         if (!link->network->static_routes && !link->dhcp_route)
 196                 return link_enter_configured(link);
 197
 198         log_debug_link(link, "setting routes");
 199
 200         LIST_FOREACH(static_routes, route, link->network->static_routes) {
 201                 r = route_configure(route, link, &route_handler);
 202                 if (r < 0) {
 203                         log_warning_link(link,
 204                                          "could not set routes: %s", strerror(-r));
 205                         link_enter_failed(link);
 206                         return r;
 207                 }
 208
 209                 link->route_messages ++;
 210         }
 211
 212         if (link->dhcp_route) {
 213                 r = route_configure(link->dhcp_route, link, &route_handler);
 214                 if (r < 0) {
 215                         log_warning_link(link,
 216                                          "could not set routes: %s", strerror(-r));
 217                         link_enter_failed(link);
 218                         return r;
 219                 }
 220
 221                 link->route_messages ++;
 222         }
 223
 224         return 0;
 225 }
 226
 227 static int address_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 228         Link *link = userdata;
 229         int r;
 230
 231         assert(m);
 232         assert(link);
 233         assert(link->ifname);
 234         assert(link->addr_messages > 0);
 235         assert(link->state == LINK_STATE_SETTING_ADDRESSES || link->state == LINK_STATE_FAILED);
 236
 237         link->addr_messages --;
 238
 239         if (link->state == LINK_STATE_FAILED)
 240                 return 1;
 241
 242         r = sd_rtnl_message_get_errno(m);
 243         if (r < 0 && r != -EEXIST)
 244                 log_struct_link(LOG_WARNING, link,
 245                                 "MESSAGE=%s: could not set address: %s",
 246                                 link->ifname, strerror(-r),
 247                                 "ERRNO=%d", -r,
 248                                 NULL);
 249
 250         if (link->addr_messages == 0) {
 251                 log_debug_link(link, "addresses set");
 252                 link_enter_set_routes(link);
 253         }
 254
 255         return 1;
 256 }
 257
 258 static int link_enter_set_addresses(Link *link) {
 259         Address *address;
 260         int r;
 261
 262         assert(link);
 263         assert(link->network);
 264         assert(link->state != _LINK_STATE_INVALID);
 265
 266         link->state = LINK_STATE_SETTING_ADDRESSES;
 267
 268         if (!link->network->static_addresses && !link->dhcp_address)
 269                 return link_enter_set_routes(link);
 270
 271         log_debug_link(link, "setting addresses");
 272
 273         LIST_FOREACH(static_addresses, address, link->network->static_addresses) {
 274                 r = address_configure(address, link, &address_handler);
 275                 if (r < 0) {
 276                         log_warning_link(link,
 277                                          "could not set addresses: %s", strerror(-r));
 278                         link_enter_failed(link);
 279                         return r;
 280                 }
 281
 282                 link->addr_messages ++;
 283         }
 284
 285         if (link->dhcp_address) {
 286                 r = address_configure(link->dhcp_address, link, &address_handler);
 287                 if (r < 0) {
 288                         log_warning_link(link,
 289                                          "could not set addresses: %s", strerror(-r));
 290                         link_enter_failed(link);
 291                         return r;
 292                 }
 293
 294                 link->addr_messages ++;
 295         }
 296
 297         return 0;
 298 }
 299
 300 static int address_drop_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 301         Link *link = userdata;
 302         int r;
 303
 304         assert(m);
 305         assert(link);
 306         assert(link->ifname);
 307
 308         if (link->state == LINK_STATE_FAILED)
 309                 return 1;
 310
 311         r = sd_rtnl_message_get_errno(m);
 312         if (r < 0 && r != -ENOENT)
 313                 log_struct_link(LOG_WARNING, link,
 314                                 "MESSAGE=%s: could not drop address: %s",
 315                                 link->ifname, strerror(-r),
 316                                 "ERRNO=%d", -r,
 317                                 NULL);
 318
 319         return 1;
 320 }
 321
 322 static int set_hostname_handler(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *ret_error) {
 323         int r;
 324
 325         r = sd_bus_message_get_errno(m);
 326         if (r < 0)
 327                 log_warning("Could not set hostname: %s", strerror(-r));
 328
 329         return 1;
 330 }
 331
 332 static int set_hostname(sd_bus *bus, const char *hostname) {
 333         _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
 334         int r = 0;
 335
 336         assert(hostname);
 337
 338         log_debug("Setting transient hostname: '%s'", hostname);
 339
 340         if (!bus) { /* TODO: replace by assert when we can rely on kdbus */
 341                 log_info("Not connected to system bus, ignoring transient hostname.");
 342                 return 0;
 343         }
 344
 345         r = sd_bus_message_new_method_call(
 346                         bus,
 347                         "org.freedesktop.hostname1",
 348                         "/org/freedesktop/hostname1",
 349                         "org.freedesktop.hostname1",
 350                         "SetHostname",
 351                         &m);
 352         if (r < 0)
 353                 return r;
 354
 355         r = sd_bus_message_append(m, "sb", hostname, false);
 356         if (r < 0)
 357                 return r;
 358
 359         r = sd_bus_call_async(bus, m, set_hostname_handler, NULL, 0, NULL);
 360         if (r < 0)
 361                 log_error("Could not set transient hostname: %s", strerror(-r));
 362
 363         return r;
 364 }
 365
 366 static int set_mtu_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 367         Link *link = userdata;
 368         int r;
 369
 370         assert(m);
 371         assert(link);
 372         assert(link->ifname);
 373
 374         if (link->state == LINK_STATE_FAILED)
 375                 return 1;
 376
 377         r = sd_rtnl_message_get_errno(m);
 378         if (r < 0)
 379                 log_struct_link(LOG_WARNING, link,
 380                                 "MESSAGE=%s: could not set MTU: %s",
 381                                 link->ifname, strerror(-r),
 382                                 "ERRNO=%d", -r,
 383                                 NULL);
 384
 385         return 1;
 386 }
 387
 388 static int link_set_mtu(Link *link, uint32_t mtu) {
 389         _cleanup_sd_rtnl_message_unref_ sd_rtnl_message *req = NULL;
 390         int r;
 391
 392         assert(link);
 393         assert(link->manager);
 394         assert(link->manager->rtnl);
 395
 396         log_debug_link(link, "setting MTU: %" PRIu32, mtu);
 397
 398         r = sd_rtnl_message_link_new(RTM_SETLINK, link->ifindex, &req);
 399         if (r < 0) {
 400                 log_error_link(link, "Could not allocate RTM_SETLINK message");
 401                 return r;
 402         }
 403
 404         r = sd_rtnl_message_append_u32(req, IFLA_MTU, mtu);
 405         if (r < 0) {
 406                 log_error_link(link, "Could not append MTU: %s", strerror(-r));
 407                 return r;
 408         }
 409
 410         r = sd_rtnl_call_async(link->manager->rtnl, req, set_mtu_handler, link, 0, NULL);
 411         if (r < 0) {
 412                 log_error_link(link,
 413                                "Could not send rtnetlink message: %s", strerror(-r));
 414                 return r;
 415         }
 416
 417         return 0;
 418 }
 419
 420 static void dhcp_handler(sd_dhcp_client *client, int event, void *userdata) {
 421         Link *link = userdata;
 422         struct in_addr address;
 423         struct in_addr netmask;
 424         struct in_addr gateway;
 425         int prefixlen;
 426         int r;
 427
 428         assert(link);
 429         assert(link->network);
 430         assert(link->manager);
 431
 432         if (link->state == LINK_STATE_FAILED)
 433                 return;
 434
 435         if (event < 0) {
 436                 log_warning_link(link, "DHCP error: %s", strerror(-event));
 437                 link_enter_failed(link);
 438                 return;
 439         }
 440
 441         if (event == DHCP_EVENT_NO_LEASE)
 442                 log_debug_link(link, "IP address in use.");
 443
 444         if (event == DHCP_EVENT_IP_CHANGE || event == DHCP_EVENT_EXPIRED ||
 445             event == DHCP_EVENT_STOP) {
 446                 if (link->dhcp_address) {
 447                         address_drop(link->dhcp_address, link, address_drop_handler);
 448
 449                         address_free(link->dhcp_address);
 450                         link->dhcp_address = NULL;
 451                 }
 452
 453                 if (link->dhcp_route) {
 454                         route_free(link->dhcp_route);
 455                         link->dhcp_route = NULL;
 456                 }
 457
 458                 if (link->network->dhcp_mtu) {
 459                         uint16_t mtu;
 460
 461                         r = sd_dhcp_client_get_mtu(client, &mtu);
 462                         if (r >= 0 && link->original_mtu != mtu) {
 463                                 r = link_set_mtu(link, link->original_mtu);
 464                                 if (r < 0) {
 465                                         log_warning_link(link, "DHCP error: could not reset MTU");
 466                                         link_enter_failed(link);
 467                                         return;
 468                                 }
 469                         }
 470                 }
 471
 472                 if (link->network->dhcp_hostname) {
 473                         r = set_hostname(link->manager->bus, "");
 474                         if (r < 0)
 475                                 log_error("Failed to reset transient hostname");
 476                 }
 477         }
 478
 479         r = sd_dhcp_client_get_address(client, &address);
 480         if (r < 0) {
 481                 log_warning_link(link, "DHCP error: no address");
 482                 link_enter_failed(link);
 483                 return;
 484         }
 485
 486         r = sd_dhcp_client_get_netmask(client, &netmask);
 487         if (r < 0) {
 488                 log_warning_link(link, "DHCP error: no netmask");
 489                 link_enter_failed(link);
 490                 return;
 491         }
 492
 493         prefixlen = sd_dhcp_client_prefixlen(&netmask);
 494         if (prefixlen < 0) {
 495                 log_warning_link(link, "DHCP error: no prefixlen");
 496                 link_enter_failed(link);
 497                 return;
 498         }
 499
 500         r = sd_dhcp_client_get_router(client, &gateway);
 501         if (r < 0) {
 502                 log_warning_link(link, "DHCP error: no router");
 503                 link_enter_failed(link);
 504                 return;
 505         }
 506
 507         if (event == DHCP_EVENT_IP_CHANGE || event == DHCP_EVENT_IP_ACQUIRE) {
 508                 _cleanup_address_free_ Address *addr = NULL;
 509                 _cleanup_route_free_ Route *rt = NULL;
 510                 struct in_addr *nameservers;
 511                 size_t nameservers_size;
 512
 513                 log_struct_link(LOG_INFO, link,
 514                                 "MESSAGE=%s: DHCPv4 address %u.%u.%u.%u/%u via %u.%u.%u.%u",
 515                                 link->ifname,
 516                                 ADDRESS_FMT_VAL(address),
 517                                 prefixlen,
 518                                 ADDRESS_FMT_VAL(gateway),
 519                                 "ADDRESS=%u.%u.%u.%u",
 520                                 ADDRESS_FMT_VAL(address),
 521                                 "PREFIXLEN=%u",
 522                                 prefixlen,
 523                                 "GATEWAY=%u.%u.%u.%u",
 524                                 ADDRESS_FMT_VAL(gateway),
 525                                 NULL);
 526
 527                 r = address_new_dynamic(&addr);
 528                 if (r < 0) {
 529                         log_error_link(link, "Could not allocate address");
 530                         link_enter_failed(link);
 531                         return;
 532                 }
 533
 534                 addr->family = AF_INET;
 535                 addr->in_addr.in = address;
 536                 addr->prefixlen = prefixlen;
 537                 addr->netmask = netmask;
 538
 539                 r = route_new_dynamic(&rt);
 540                 if (r < 0) {
 541                         log_error_link(link, "Could not allocate route");
 542                         link_enter_failed(link);
 543                         return;
 544                 }
 545
 546                 rt->family = AF_INET;
 547                 rt->in_addr.in = gateway;
 548
 549                 link->dhcp_address = addr;
 550                 link->dhcp_route = rt;
 551                 addr = NULL;
 552                 rt = NULL;
 553
 554                 if (link->network->dhcp_dns) {
 555                         r = sd_dhcp_client_get_dns(client, &nameservers, &nameservers_size);
 556                         if (r >= 0) {
 557                                 r = manager_update_resolv_conf(link->manager);
 558                                 if (r < 0)
 559                                         log_error("Failed to update resolv.conf");
 560                         }
 561                 }
 562
 563                 if (link->network->dhcp_mtu) {
 564                         uint16_t mtu;
 565
 566                         r = sd_dhcp_client_get_mtu(client, &mtu);
 567                         if (r >= 0) {
 568                                 r = link_set_mtu(link, mtu);
 569                                 if (r < 0)
 570                                         log_error_link(link, "Failed to set MTU "
 571                                                              "to %" PRIu16, mtu);
 572                         }
 573                 }
 574
 575                 if (link->network->dhcp_hostname) {
 576                         const char *hostname;
 577
 578                         r = sd_dhcp_client_get_hostname(client, &hostname);
 579                         if (r >= 0) {
 580                                 r = set_hostname(link->manager->bus, hostname);
 581                                 if (r < 0)
 582                                         log_error("Failed to set transient hostname "
 583                                                   "to '%s'", hostname);
 584                         }
 585                 }
 586
 587                 link_enter_set_addresses(link);
 588         }
 589
 590         return;
 591 }
 592
 593 static int link_acquire_conf(Link *link) {
 594         int r;
 595
 596         assert(link);
 597         assert(link->network);
 598         assert(link->network->dhcp);
 599         assert(link->manager);
 600         assert(link->manager->event);
 601
 602         if (!link->dhcp) {
 603                 r = sd_dhcp_client_new(&link->dhcp);
 604                 if (r < 0)
 605                         return r;
 606
 607                 r = sd_dhcp_client_attach_event(link->dhcp, NULL, 0);
 608                 if (r < 0)
 609                         return r;
 610
 611                 r = sd_dhcp_client_set_index(link->dhcp, link->ifindex);
 612                 if (r < 0)
 613                         return r;
 614
 615                 r = sd_dhcp_client_set_mac(link->dhcp, &link->mac);
 616                 if (r < 0)
 617                         return r;
 618
 619                 r = sd_dhcp_client_set_callback(link->dhcp, dhcp_handler, link);
 620                 if (r < 0)
 621                         return r;
 622
 623                 if (link->network->dhcp_mtu) {
 624                         r = sd_dhcp_client_set_request_option(link->dhcp, 26);
 625                         if (r < 0)
 626                                 return r;
 627                 }
 628         }
 629
 630         log_debug_link(link, "acquiring DHCPv4 lease");
 631
 632         r = sd_dhcp_client_start(link->dhcp);
 633         if (r < 0)
 634                 return r;
 635
 636         return 0;
 637 }
 638
 639 static int link_update_flags(Link *link, unsigned flags) {
 640         int r;
 641
 642         assert(link);
 643         assert(link->network);
 644
 645         if (link->state == LINK_STATE_FAILED)
 646                 return 0;
 647
 648         if (link->flags == flags) {
 649                 log_debug_link(link, "link status unchanged: %#.8x", flags);
 650                 return 0;
 651         }
 652
 653         if ((link->flags & IFF_UP) != (flags & IFF_UP))
 654                 log_info_link(link,
 655                               "link is %s", flags & IFF_UP ? "up": "down");
 656
 657         if ((link->flags & IFF_LOWER_UP) != (flags & IFF_LOWER_UP)) {
 658                 if (flags & IFF_LOWER_UP) {
 659                         log_info_link(link, "carrier on");
 660
 661                         if (link->network->dhcp) {
 662                                 r = link_acquire_conf(link);
 663                                 if (r < 0) {
 664                                         log_warning_link(link, "Could not acquire DHCPv4 lease: %s", strerror(-r));
 665                                         link_enter_failed(link);
 666                                         return r;
 667                                 }
 668                         }
 669                 } else {
 670                         log_info_link(link, "carrier off");
 671
 672                         if (link->network->dhcp) {
 673                                 r = sd_dhcp_client_stop(link->dhcp);
 674                                 if (r < 0) {
 675                                         log_warning_link(link, "Could not stop DHCPv4 client: %s", strerror(-r));
 676                                         link_enter_failed(link);
 677                                         return r;
 678                                 }
 679                         }
 680                 }
 681         }
 682
 683         log_debug_link(link,
 684                        "link status updated: %#.8x -> %#.8x", link->flags, flags);
 685
 686         link->flags = flags;
 687
 688         return 0;
 689 }
 690
 691 static int link_up_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 692         Link *link = userdata;
 693         int r;
 694
 695         assert(link);
 696
 697         if (link->state == LINK_STATE_FAILED)
 698                 return 1;
 699
 700         r = sd_rtnl_message_get_errno(m);
 701         if (r < 0) {
 702                 log_struct_link(LOG_ERR, link,
 703                                 "MESSAGE=%s: could not bring up interface: %s",
 704                                 link->ifname, strerror(-r),
 705                                 "ERRNO=%d", -r,
 706                                 NULL);
 707                 link_enter_failed(link);
 708                 return 1;
 709         }
 710
 711         link_update_flags(link, link->flags | IFF_UP);
 712
 713         return 1;
 714 }
 715
 716 static int link_up(Link *link) {
 717         _cleanup_sd_rtnl_message_unref_ sd_rtnl_message *req = NULL;
 718         int r;
 719
 720         assert(link);
 721         assert(link->manager);
 722         assert(link->manager->rtnl);
 723
 724         log_debug_link(link, "bringing link up");
 725
 726         r = sd_rtnl_message_link_new(RTM_SETLINK, link->ifindex, &req);
 727         if (r < 0) {
 728                 log_error_link(link, "Could not allocate RTM_SETLINK message");
 729                 return r;
 730         }
 731
 732         r = sd_rtnl_message_link_set_flags(req, IFF_UP, IFF_UP);
 733         if (r < 0) {
 734                 log_error_link(link, "Could not set link flags: %s", strerror(-r));
 735                 return r;
 736         }
 737
 738         r = sd_rtnl_call_async(link->manager->rtnl, req, link_up_handler, link, 0, NULL);
 739         if (r < 0) {
 740                 log_error_link(link,
 741                                "Could not send rtnetlink message: %s", strerror(-r));
 742                 return r;
 743         }
 744
 745         return 0;
 746 }
 747
 748 static int link_enslaved(Link *link) {
 749         int r;
 750
 751         assert(link);
 752         assert(link->state == LINK_STATE_ENSLAVING);
 753         assert(link->network);
 754
 755         r = link_up(link);
 756         if (r < 0) {
 757                 link_enter_failed(link);
 758                 return r;
 759         }
 760
 761         if (!link->network->dhcp)
 762                 return link_enter_set_addresses(link);
 763
 764         return 0;
 765 }
 766
 767 static int enslave_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 768         Link *link = userdata;
 769         int r;
 770
 771         assert(link);
 772         assert(link->state == LINK_STATE_ENSLAVING || link->state == LINK_STATE_FAILED);
 773         assert(link->network);
 774
 775         link->enslaving --;
 776
 777         if (link->state == LINK_STATE_FAILED)
 778                 return 1;
 779
 780         r = sd_rtnl_message_get_errno(m);
 781         if (r < 0) {
 782                 log_struct_link(LOG_ERR, link,
 783                                 "MESSAGE=%s: could not enslave: %s",
 784                                 link->ifname, strerror(-r),
 785                                 "ERRNO=%d", -r,
 786                                 NULL);
 787                 link_enter_failed(link);
 788                 return 1;
 789         }
 790
 791         log_debug_link(link, "enslaved");
 792
 793         if (link->enslaving == 0)
 794                 link_enslaved(link);
 795
 796         return 1;
 797 }
 798
 799 static int link_enter_enslave(Link *link) {
 800         int r;
 801
 802         assert(link);
 803         assert(link->network);
 804         assert(link->state == _LINK_STATE_INVALID);
 805
 806         link->state = LINK_STATE_ENSLAVING;
 807
 808         if (!link->network->bridge && !link->network->bond && !link->network->vlan)
 809                 return link_enslaved(link);
 810
 811         if (link->network->bridge) {
 812                 log_struct_link(LOG_DEBUG, link,
 813                                 "MESSAGE=%s: enslaving by '%s'",
 814                                 link->ifname, link->network->bridge->name,
 815                                 NETDEV(link->network->bridge),
 816                                 NULL);
 817
 818                 r = netdev_enslave(link->network->bridge, link, &enslave_handler);
 819                 if (r < 0) {
 820                         log_struct_link(LOG_WARNING, link,
 821                                         "MESSAGE=%s: could not enslave by '%s': %s",
 822                                         link->ifname, link->network->bridge->name, strerror(-r),
 823                                         NETDEV(link->network->bridge),
 824                                         NULL);
 825                         link_enter_failed(link);
 826                         return r;
 827                 }
 828
 829                 link->enslaving ++;
 830         }
 831
 832         if (link->network->vlan) {
 833                 log_struct_link(LOG_DEBUG, link,
 834                                 "MESSAGE=%s: enslaving by '%s'",
 835                                 link->ifname, link->network->vlan->name,
 836                                 NETDEV(link->network->vlan),
 837                                 NULL);
 838
 839                 r = netdev_enslave(link->network->vlan, link, &enslave_handler);
 840                 if (r < 0) {
 841                         log_struct_link(LOG_WARNING, link,
 842                                         "MESSAGE=%s: could not enslave by '%s': %s",
 843                                         link->ifname, link->network->vlan->name,
 844                                         strerror(-r), NETDEV(link->network->vlan),
 845                                         NULL);
 846                         link_enter_failed(link);
 847                         return r;
 848                 }
 849
 850                 link->enslaving ++;
 851         }
 852
 853         return 0;
 854 }
 855
 856 static int link_get_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 857         Link *link = userdata;
 858         int r;
 859
 860         assert(link);
 861
 862         if (link->state == LINK_STATE_FAILED)
 863                 return 1;
 864
 865         r = sd_rtnl_message_get_errno(m);
 866         if (r < 0) {
 867                 log_struct_link(LOG_ERR, link,
 868                                 "MESSAGE=%s: could not get state: %s",
 869                                 link->ifname, strerror(-r),
 870                                 "ERRNO=%d", -r,
 871                                 NULL);
 872                 link_enter_failed(link);
 873                 return 1;
 874         }
 875
 876         log_debug_link(link, "got link state");
 877
 878         link_update(link, m);
 879
 880         return 1;
 881 }
 882
 883 static int link_get(Link *link) {
 884         _cleanup_sd_rtnl_message_unref_ sd_rtnl_message *req = NULL;
 885         int r;
 886
 887         assert(link);
 888         assert(link->manager);
 889         assert(link->manager->rtnl);
 890
 891         log_debug_link(link, "requesting link status");
 892
 893         r = sd_rtnl_message_link_new(RTM_GETLINK, link->ifindex, &req);
 894         if (r < 0) {
 895                 log_error_link(link, "Could not allocate RTM_GETLINK message");
 896                 return r;
 897         }
 898
 899         r = sd_rtnl_call_async(link->manager->rtnl, req, link_get_handler, link, 0, NULL);
 900         if (r < 0) {
 901                 log_error_link(link,
 902                                "Could not send rtnetlink message: %s", strerror(-r));
 903                 return r;
 904         }
 905
 906         return 0;
 907 }
 908
 909 int link_configure(Link *link) {
 910         int r;
 911
 912         assert(link);
 913         assert(link->network);
 914         assert(link->state == _LINK_STATE_INVALID);
 915
 916         r = link_get(link);
 917         if (r < 0) {
 918                 link_enter_failed(link);
 919                 return r;
 920         }
 921
 922         return link_enter_enslave(link);
 923 }
 924
 925 int link_update(Link *link, sd_rtnl_message *m) {
 926         unsigned flags;
 927         void *data;
 928         uint16_t type;
 929         int r;
 930
 931         assert(link);
 932         assert(m);
 933
 934         if (link->state == LINK_STATE_FAILED)
 935                 return 0;
 936
 937         r = sd_rtnl_message_link_get_flags(m, &flags);
 938         if (r < 0) {
 939                 log_warning_link(link, "Could not get link flags");
 940                 return r;
 941         }
 942
 943         while (sd_rtnl_message_read(m, &type, &data) > 0) {
 944                 if (type == IFLA_MTU && link->network->dhcp &&
 945                     link->network->dhcp_mtu && !link->original_mtu) {
 946                         link->original_mtu = *(uint16_t *) data;
 947                         log_debug_link(link, "saved original MTU: %" PRIu16,
 948                                        link->original_mtu);
 949                 }
 950         }
 951
 952         return link_update_flags(link, flags);
 953 }