git.ozlabs.org Git - petitboot/blob - discover/network.c

   1
   2 #include <stdbool.h>
   3 #include <stdint.h>
   4 #include <string.h>
   5 #include <stdlib.h>
   6 #include <errno.h>
   7 #include <sys/socket.h>
   8 #include <linux/if.h>
   9 #include <linux/netlink.h>
  10 #include <linux/rtnetlink.h>
  11 #include <i18n/i18n.h>
  12
  13 #include <log/log.h>
  14 #include <list/list.h>
  15 #include <file/file.h>
  16 #include <types/types.h>
  17 #include <talloc/talloc.h>
  18 #include <waiter/waiter.h>
  19 #include <process/process.h>
  20 #include <system/system.h>
  21
  22 #include "network.h"
  23 #include "sysinfo.h"
  24 #include "platform.h"
  25 #include "device-handler.h"
  26 #include "paths.h"
  27
  28 #define HWADDR_SIZE     6
  29 #define PIDFILE_BASE    (LOCAL_STATE_DIR "/petitboot/")
  30 #define INITIAL_BUFSIZE 4096
  31
  32 #define for_each_nlmsg(buf, nlmsg, len) \
  33         for (nlmsg = (struct nlmsghdr *)buf; \
  34                 NLMSG_OK(nlmsg, len) && nlmsg->nlmsg_type != NLMSG_DONE; \
  35                 nlmsg = NLMSG_NEXT(nlmsg, len))
  36
  37 #define for_each_rta(buf, rta, attrlen) \
  38         for (rta = (struct rtattr *)(buf); RTA_OK(rta, attrlen); \
  39                         rta = RTA_NEXT(rta, attrlen))
  40
  41
  42 struct interface {
  43         int     ifindex;
  44         char    name[IFNAMSIZ];
  45         uint8_t hwaddr[HWADDR_SIZE];
  46
  47         enum {
  48                 IFSTATE_NEW,
  49                 IFSTATE_UP_WAITING_LINK,
  50                 IFSTATE_CONFIGURED,
  51                 IFSTATE_IGNORED,
  52         } state;
  53
  54         struct list_item list;
  55         struct process *udhcpc_process;
  56         struct discover_device *dev;
  57         bool ready;
  58 };
  59
  60 struct network {
  61         struct list             interfaces;
  62         struct device_handler   *handler;
  63         struct waiter           *waiter;
  64         int                     netlink_sd;
  65         void                    *netlink_buf;
  66         unsigned int            netlink_buf_size;
  67         bool                    manual_config;
  68         bool                    dry_run;
  69 };
  70
  71 static char *mac_bytes_to_string(void *ctx, uint8_t *addr, int len)
  72 {
  73         const int l = strlen("xx:");
  74         char *buf;
  75         int i;
  76
  77         if (len <= 0)
  78                 return talloc_strdup(ctx, "");
  79
  80         buf = talloc_array(ctx, char, (len * l) + 1);
  81
  82         for (i = 0; i < len; i++)
  83                 sprintf(buf + (l * i), "%02x:", addr[i]);
  84
  85         *(buf + (l * len) - 1) = '\0';
  86
  87         return buf;
  88 }
  89
  90 static const struct interface_config *find_config_by_hwaddr(
  91                 uint8_t *hwaddr)
  92 {
  93         const struct config *config;
  94         unsigned int i;
  95
  96         config = config_get();
  97         if (!config)
  98                 return NULL;
  99
 100         for (i = 0; i < config->network.n_interfaces; i++) {
 101                 struct interface_config *ifconf = config->network.interfaces[i];
 102
 103                 if (!memcmp(ifconf->hwaddr, hwaddr, HWADDR_SIZE))
 104                         return ifconf;
 105         }
 106
 107         return NULL;
 108 }
 109
 110 static struct interface *find_interface_by_ifindex(struct network *network,
 111                 int ifindex)
 112 {
 113         struct interface *interface;
 114
 115         list_for_each_entry(&network->interfaces, interface, list)
 116                 if (interface->ifindex == ifindex)
 117                         return interface;
 118
 119         return NULL;
 120 }
 121
 122 static struct interface *find_interface_by_name(struct network *network,
 123                 const char *name)
 124 {
 125         struct interface *interface;
 126
 127         list_for_each_entry(&network->interfaces, interface, list)
 128                 if (!strcmp(interface->name, name))
 129                         return interface;
 130
 131         return NULL;
 132 }
 133
 134 static struct interface *find_interface_by_uuid(struct network *network,
 135                 const char *uuid)
 136 {
 137         struct interface *interface;
 138         char *mac;
 139
 140         list_for_each_entry(&network->interfaces, interface, list) {
 141                 mac = mac_bytes_to_string(interface, interface->hwaddr,
 142                                         sizeof(interface->hwaddr));
 143                 if (!strcmp(mac, uuid)) {
 144                         talloc_free(mac);
 145                         return interface;
 146                 }
 147                 talloc_free(mac);
 148         }
 149
 150         return NULL;
 151 }
 152
 153 uint8_t *find_mac_by_name(void *ctx, struct network *network,
 154                 const char *name)
 155 {
 156         struct interface *interface;
 157
 158         interface = find_interface_by_name(network, name);
 159         if (!interface)
 160                 return NULL;
 161
 162         return talloc_memdup(ctx, &interface->hwaddr,
 163                              sizeof(uint8_t) * HWADDR_SIZE);
 164 }
 165
 166 static int network_init_netlink(struct network *network)
 167 {
 168         struct sockaddr_nl addr;
 169         int rc;
 170
 171         memset(&addr, 0, sizeof(addr));
 172         addr.nl_family = AF_NETLINK;
 173         addr.nl_groups = RTMGRP_LINK;
 174
 175         network->netlink_sd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
 176         if (network->netlink_sd < 0) {
 177                 perror("socket(AF_NETLINK)");
 178                 return -1;
 179         }
 180
 181         rc = bind(network->netlink_sd, (struct sockaddr *)&addr, sizeof(addr));
 182         if (rc) {
 183                 perror("bind(sockaddr_nl)");
 184                 close(network->netlink_sd);
 185                 return -1;
 186         }
 187
 188         network->netlink_buf_size = INITIAL_BUFSIZE;
 189         network->netlink_buf = talloc_array(network, char,
 190                                 network->netlink_buf_size);
 191
 192         return 0;
 193 }
 194
 195 static int network_send_link_query(struct network *network)
 196 {
 197         int rc;
 198         struct {
 199                 struct nlmsghdr nlmsg;
 200                 struct rtgenmsg rtmsg;
 201         } msg;
 202
 203         memset(&msg, 0, sizeof(msg));
 204
 205         msg.nlmsg.nlmsg_len = sizeof(msg);
 206         msg.nlmsg.nlmsg_type = RTM_GETLINK;
 207         msg.nlmsg.nlmsg_flags = NLM_F_REQUEST | NLM_F_ROOT;
 208         msg.nlmsg.nlmsg_seq = 0;
 209         msg.nlmsg.nlmsg_pid = 0;
 210         msg.rtmsg.rtgen_family = AF_UNSPEC;
 211
 212         rc = send(network->netlink_sd, &msg, sizeof(msg), MSG_NOSIGNAL);
 213         if (rc != sizeof(msg))
 214                 return -1;
 215
 216         return 0;
 217 }
 218
 219 static void create_interface_dev(struct network *network,
 220                 struct interface *interface)
 221 {
 222         char *uuid = mac_bytes_to_string(interface, interface->hwaddr,
 223                                                 sizeof(interface->hwaddr));
 224
 225         interface->dev = discover_device_create(network->handler, uuid,
 226                                                 interface->name);
 227         interface->dev->device->type = DEVICE_TYPE_NETWORK;
 228         device_handler_add_device(network->handler, interface->dev);
 229         talloc_free(uuid);
 230 }
 231
 232 static void remove_interface(struct network *network,
 233                 struct interface *interface)
 234 {
 235         if (interface->dev)
 236                 device_handler_remove(network->handler, interface->dev);
 237         list_remove(&interface->list);
 238         talloc_free(interface);
 239 }
 240
 241 void network_register_device(struct network *network,
 242                 struct discover_device *dev)
 243 {
 244         struct interface *iface;
 245
 246         if (dev->uuid)
 247                 iface = find_interface_by_uuid(network, dev->uuid);
 248         else
 249                 iface = find_interface_by_name(network, dev->label);
 250         if (!iface)
 251                 return;
 252
 253         iface->dev = dev;
 254         dev->uuid = mac_bytes_to_string(iface->dev, iface->hwaddr,
 255                         sizeof(iface->hwaddr));
 256 }
 257
 258 void network_unregister_device(struct network *network,
 259                 struct discover_device *dev)
 260 {
 261         struct interface *iface;
 262
 263         iface = find_interface_by_uuid(network, dev->uuid);
 264         if (!iface)
 265                 return;
 266
 267         iface->dev = NULL;
 268 }
 269
 270 static int interface_change(struct interface *interface, bool up)
 271 {
 272         const char *statestr = up ? "up" : "down";
 273         int rc;
 274
 275         if (!up && interface->udhcpc_process) {
 276                 /* we don't care about the callback from here */
 277                 interface->udhcpc_process->exit_cb = NULL;
 278                 interface->udhcpc_process->data = NULL;
 279                 process_stop_async(interface->udhcpc_process);
 280                 process_release(interface->udhcpc_process);
 281         }
 282
 283         if (!up) {
 284                 rc = process_run_simple(interface, pb_system_apps.ip,
 285                                 "address", "flush", "dev", interface->name,
 286                                 NULL);
 287                 if (rc)
 288                         pb_log("failed to flush addresses from interface %s\n",
 289                                 interface->name);
 290         }
 291
 292         rc = process_run_simple(interface, pb_system_apps.ip,
 293                         "link", "set", interface->name, statestr, NULL);
 294         if (rc) {
 295                 pb_log("failed to bring interface %s %s\n", interface->name,
 296                                 statestr);
 297                 return -1;
 298         }
 299         return 0;
 300 }
 301
 302 static int interface_up(struct interface *interface)
 303 {
 304         return interface_change(interface, true);
 305 }
 306
 307 static int interface_down(struct interface *interface)
 308 {
 309         return interface_change(interface, false);
 310 }
 311
 312 static void udhcpc_process_exit(struct process *process)
 313 {
 314         struct interface *interface = process->data;
 315         pb_debug("udhcp client [pid %d] for interface %s exited, rc %d\n",
 316                         process->pid, interface->name, process->exit_status);
 317         interface->udhcpc_process = NULL;
 318         process_release(process);
 319 }
 320
 321 static void configure_interface_dhcp(struct network *network,
 322                 struct interface *interface)
 323 {
 324         const struct platform *platform;
 325         char pidfile[256], id[10];
 326         struct process *process;
 327         int rc;
 328         const char *argv[] = {
 329                 pb_system_apps.udhcpc,
 330                 "-R",
 331                 "-f",
 332                 "-O", "pxeconffile",
 333                 "-O", "pxepathprefix",
 334                 "-O", "reboottime",
 335                 "-p", pidfile,
 336                 "-i", interface->name,
 337                 "-x", id, /* [11,12] - dhcp client identifier */
 338                 NULL,
 339         };
 340
 341         device_handler_status_dev_info(network->handler, interface->dev,
 342                         _("Configuring with DHCP"));
 343
 344         snprintf(pidfile, sizeof(pidfile), "%s/udhcpc-%s.pid",
 345                         PIDFILE_BASE, interface->name);
 346
 347         platform = platform_get();
 348         if (platform && platform->dhcp_arch_id != 0xffff)
 349                 snprintf(id, sizeof(id), "0x5d:%04x", platform->dhcp_arch_id);
 350         else
 351                 argv[11] = NULL;
 352
 353         process = process_create(interface);
 354
 355         process->path = pb_system_apps.udhcpc;
 356         process->argv = argv;
 357         process->exit_cb = udhcpc_process_exit;
 358         process->data = interface;
 359
 360         rc = process_run_async(process);
 361
 362         if (rc)
 363                 process_release(process);
 364         else
 365                 interface->udhcpc_process = process;
 366
 367         return;
 368 }
 369
 370 static void configure_interface_static(struct network *network,
 371                 struct interface *interface,
 372                 const struct interface_config *config)
 373 {
 374         int rc;
 375
 376         device_handler_status_dev_info(network->handler, interface->dev,
 377                         _("Configuring with static address (ip: %s)"),
 378                         config->static_config.address);
 379
 380         rc = process_run_simple(interface, pb_system_apps.ip,
 381                         "address", "add", config->static_config.address,
 382                         "dev", interface->name, NULL);
 383
 384
 385         if (rc) {
 386                 pb_log("failed to add address %s to interface %s\n",
 387                                 config->static_config.address,
 388                                 interface->name);
 389                 return;
 390         }
 391
 392         system_info_set_interface_address(sizeof(interface->hwaddr),
 393                                 interface->hwaddr,
 394                                 config->static_config.address);
 395
 396         /* we need the interface up before we can route through it */
 397         rc = interface_up(interface);
 398         if (rc)
 399                 return;
 400
 401         if (config->static_config.gateway)
 402                 rc = process_run_simple(interface, pb_system_apps.ip,
 403                                 "route", "add", "default",
 404                                 "via", config->static_config.gateway,
 405                                 NULL);
 406
 407         if (rc) {
 408                 pb_log("failed to add default route %s on interface %s\n",
 409                                 config->static_config.gateway,
 410                                 interface->name);
 411         }
 412
 413         if (config->static_config.url) {
 414                 pb_log("config URL %s\n", config->static_config.url);
 415                 device_handler_process_url(network->handler,
 416                                 config->static_config.url,
 417                                 mac_bytes_to_string(interface->dev,
 418                                                 interface->hwaddr,
 419                                                 sizeof(interface->hwaddr)),
 420                                 config->static_config.address);
 421                 device_handler_start_requery_timeout(network->handler,
 422                                 interface->dev, -1);
 423         }
 424
 425         return;
 426 }
 427
 428 static void configure_interface(struct network *network,
 429                 struct interface *interface, bool up, bool link)
 430 {
 431         const struct interface_config *config = NULL;
 432
 433         if (interface->state == IFSTATE_IGNORED)
 434                 return;
 435
 436         /* old interface? check that we're still up and running */
 437         if (interface->state == IFSTATE_CONFIGURED) {
 438                 if (!up)
 439                         interface->state = IFSTATE_NEW;
 440                 else if (!link)
 441                         interface->state = IFSTATE_UP_WAITING_LINK;
 442                 else {
 443                         pb_debug("network: skipping configured interface %s\n",
 444                                         interface->name);
 445                         return;
 446                 }
 447         }
 448
 449         /* always up the lookback, no other handling required */
 450         if (!strcmp(interface->name, "lo")) {
 451                 if (interface->state == IFSTATE_NEW)
 452                         interface_up(interface);
 453                 interface->state = IFSTATE_CONFIGURED;
 454                 return;
 455         }
 456
 457         config = find_config_by_hwaddr(interface->hwaddr);
 458         if (config && config->ignore) {
 459                 pb_log("network: ignoring interface %s\n", interface->name);
 460                 interface->state = IFSTATE_IGNORED;
 461                 return;
 462         }
 463
 464         /* if we're in manual config mode, we need an interface configuration */
 465         if (network->manual_config && !config) {
 466                 interface->state = IFSTATE_IGNORED;
 467                 pb_log("network: skipping %s: manual config mode, "
 468                                 "but no config for this interface\n",
 469                                 interface->name);
 470                 return;
 471         }
 472
 473         /* new interface? bring up to the point so we can detect a link */
 474         if (interface->state == IFSTATE_NEW) {
 475                 if (!up) {
 476                         interface_up(interface);
 477                         pb_log("network: bringing up interface %s\n",
 478                                         interface->name);
 479                         return;
 480
 481                 } else if (!link) {
 482                         interface->state = IFSTATE_UP_WAITING_LINK;
 483                 }
 484         }
 485
 486         /* no link? wait for a notification */
 487         if (interface->state == IFSTATE_UP_WAITING_LINK && !link)
 488                 return;
 489
 490         pb_log("network: configuring interface %s\n", interface->name);
 491
 492         if (!config || config->method == CONFIG_METHOD_DHCP) {
 493                 configure_interface_dhcp(network, interface);
 494
 495         } else if (config->method == CONFIG_METHOD_STATIC) {
 496                 configure_interface_static(network, interface, config);
 497                 /* Nothing left to do for static interfaces */
 498                 pending_network_jobs_start();
 499         }
 500
 501         interface->state = IFSTATE_CONFIGURED;
 502 }
 503
 504 void network_requery_device(struct network *network,
 505                 struct discover_device *dev)
 506 {
 507         const struct interface_config *config;
 508         struct interface *interface;
 509
 510         interface = find_interface_by_uuid(network, dev->uuid);
 511         if (!interface)
 512                 return;
 513
 514         if (interface->udhcpc_process) {
 515                 interface->udhcpc_process->exit_cb = NULL;
 516                 interface->udhcpc_process->data = NULL;
 517                 process_stop_async(interface->udhcpc_process);
 518                 process_release(interface->udhcpc_process);
 519         }
 520
 521         config = find_config_by_hwaddr(interface->hwaddr);
 522
 523         if (config && config->ignore)
 524                 return;
 525
 526         if (!config || config->method == CONFIG_METHOD_DHCP) {
 527                 /* Restart DHCP. Once we acquire a lease, we'll re-start
 528                  * the requery timeout (based on any reboottime DHCP option)
 529                  */
 530                 configure_interface_dhcp(network, interface);
 531
 532         } else if (config->method == CONFIG_METHOD_STATIC &&
 533                         config->static_config.url) {
 534                 /* Redownload statically-provided URL, and manually restart
 535                  * requery timeout */
 536                 device_handler_process_url(network->handler,
 537                                 config->static_config.url,
 538                                 mac_bytes_to_string(interface->dev,
 539                                                 interface->hwaddr,
 540                                                 sizeof(interface->hwaddr)),
 541                                 config->static_config.address);
 542                 device_handler_start_requery_timeout(network->handler,
 543                                 dev, -1);
 544         }
 545 }
 546
 547 static int network_handle_nlmsg(struct network *network, struct nlmsghdr *nlmsg)
 548 {
 549         bool have_ifaddr, have_ifname;
 550         struct interface *interface, *tmp;
 551         struct ifinfomsg *info;
 552         struct rtattr *attr;
 553         unsigned int mtu;
 554         uint8_t ifaddr[6];
 555         char ifname[IFNAMSIZ];
 556         int attrlen, type;
 557
 558
 559         /* we're only interested in NEWLINK messages */
 560         type = nlmsg->nlmsg_type;
 561         if (!(type == RTM_NEWLINK || type == RTM_DELLINK))
 562                 return 0;
 563
 564         info = NLMSG_DATA(nlmsg);
 565
 566         have_ifaddr = have_ifname = false;
 567         mtu = 1;
 568
 569         attrlen = nlmsg->nlmsg_len - sizeof(*info);
 570
 571         /* extract the interface name and hardware address attributes */
 572         for_each_rta(info + 1, attr, attrlen) {
 573                 void *data = RTA_DATA(attr);
 574
 575                 switch (attr->rta_type) {
 576                 case IFLA_ADDRESS:
 577                         memcpy(ifaddr, data, sizeof(ifaddr));
 578                         have_ifaddr = true;
 579                         break;
 580
 581                 case IFLA_IFNAME:
 582                         strncpy(ifname, data, IFNAMSIZ);
 583                         ifname[IFNAMSIZ - 1] = '\0';
 584                         have_ifname = true;
 585                         break;
 586
 587                 case IFLA_MTU:
 588                         mtu = *(unsigned int *)data;
 589                         break;
 590                 }
 591         }
 592
 593         if (!have_ifaddr || !have_ifname)
 594                 return -1;
 595
 596         if (type == RTM_DELLINK || mtu == 0) {
 597                 interface = find_interface_by_ifindex(network, info->ifi_index);
 598                 if (!interface)
 599                         return 0;
 600                 pb_log("network: interface %s removed\n", interface->name);
 601                 remove_interface(network, interface);
 602                 return 0;
 603         }
 604
 605         /* ignore the default tun device in some environments */
 606         if (strncmp(ifname, "tun", strlen("tun")) == 0)
 607                 return 0;
 608
 609         interface = find_interface_by_ifindex(network, info->ifi_index);
 610         if (!interface) {
 611                 interface = talloc_zero(network, struct interface);
 612                 interface->ifindex = info->ifi_index;
 613                 interface->state = IFSTATE_NEW;
 614                 memcpy(interface->hwaddr, ifaddr, sizeof(interface->hwaddr));
 615                 strncpy(interface->name, ifname, sizeof(interface->name));
 616
 617                 list_for_each_entry(&network->interfaces, tmp, list)
 618                         if (memcmp(interface->hwaddr, tmp->hwaddr,
 619                                    sizeof(interface->hwaddr)) == 0) {
 620                                 pb_log("%s: %s has duplicate MAC address, ignoring\n",
 621                                        __func__, interface->name);
 622                                 talloc_free(interface);
 623                                 return -1;
 624                         }
 625
 626                 list_add(&network->interfaces, &interface->list);
 627                 create_interface_dev(network, interface);
 628         }
 629
 630         /* A repeated RTM_NEWLINK can represent an interface name change */
 631         if (strncmp(interface->name, ifname, IFNAMSIZ)) {
 632                 pb_debug("ifname update: %s -> %s\n", interface->name, ifname);
 633                 strncpy(interface->name, ifname, sizeof(interface->name));
 634                 talloc_free(interface->dev->device->id);
 635                 interface->dev->device->id =
 636                         talloc_strdup(interface->dev->device, ifname);
 637         }
 638
 639         /* notify the sysinfo code about changes to this interface */
 640         if (strcmp(interface->name, "lo"))
 641                 system_info_register_interface(
 642                                 sizeof(interface->hwaddr),
 643                                 interface->hwaddr, interface->name,
 644                                 info->ifi_flags & IFF_LOWER_UP);
 645
 646         if (!interface->dev)
 647                 create_interface_dev(network, interface);
 648
 649         if (!interface->ready && strncmp(interface->name, "lo", strlen("lo"))) {
 650                 pb_log("%s not marked ready yet\n", interface->name);
 651                 return 0;
 652         }
 653
 654         configure_interface(network, interface,
 655                         info->ifi_flags & IFF_UP,
 656                         info->ifi_flags & IFF_LOWER_UP);
 657
 658         return 0;
 659 }
 660
 661 void network_mark_interface_ready(struct device_handler *handler,
 662                 int ifindex, const char *ifname, uint8_t *mac, int hwsize)
 663 {
 664         struct network *network = device_handler_get_network(handler);
 665         struct interface *interface, *tmp = NULL;
 666         char *macstr;
 667
 668         if (!network) {
 669                 pb_log("Network not ready - can not mark interface ready\n");
 670                 return;
 671         }
 672
 673         if (hwsize != HWADDR_SIZE)
 674                 return;
 675
 676         if (strncmp(ifname, "lo", strlen("lo")) == 0)
 677                 return;
 678
 679         interface = find_interface_by_ifindex(network, ifindex);
 680         if (!interface) {
 681                 pb_debug("Creating ready interface %d - %s\n",
 682                                 ifindex, ifname);
 683                 interface = talloc_zero(network, struct interface);
 684                 interface->ifindex = ifindex;
 685                 interface->state = IFSTATE_NEW;
 686                 memcpy(interface->hwaddr, mac, HWADDR_SIZE);
 687                 strncpy(interface->name, ifname, sizeof(interface->name) - 1);
 688
 689                 list_for_each_entry(&network->interfaces, tmp, list)
 690                         if (memcmp(interface->hwaddr, tmp->hwaddr,
 691                                    sizeof(interface->hwaddr)) == 0) {
 692                                 pb_log("%s: %s has duplicate MAC address, ignoring\n",
 693                                        __func__, interface->name);
 694                                 talloc_free(interface);
 695                                 return;
 696                         }
 697
 698                 list_add(&network->interfaces, &interface->list);
 699                 create_interface_dev(network, interface);
 700         }
 701
 702         if (interface->ready) {
 703                 pb_log("%s already ready\n", interface->name);
 704                 return;
 705         }
 706
 707         if (strncmp(interface->name, ifname, strlen(ifname)) != 0) {
 708                 pb_debug("ifname update from udev: %s -> %s\n", interface->name, ifname);
 709                 strncpy(interface->name, ifname, sizeof(interface->name) - 1);
 710                 talloc_free(interface->dev->device->id);
 711                 interface->dev->device->id =
 712                         talloc_strdup(interface->dev->device, ifname);
 713         }
 714
 715         if (memcmp(interface->hwaddr, mac, HWADDR_SIZE) != 0) {
 716                 macstr = mac_bytes_to_string(interface, mac, hwsize);
 717                 pb_log("Warning - new MAC for interface %d does not match: %s\n",
 718                                 ifindex, macstr);
 719                 talloc_free(macstr);
 720         }
 721
 722         pb_log("Interface %s ready\n", ifname);
 723         interface->ready = true;
 724         configure_interface(network, interface, false, false);
 725 }
 726
 727 static int network_netlink_process(void *arg)
 728 {
 729         struct network *network = arg;
 730         struct nlmsghdr *nlmsg;
 731         struct msghdr msg;
 732         struct iovec iov;
 733         unsigned int len;
 734         int rc, flags;
 735
 736         memset(&msg, 0, sizeof(msg));
 737         msg.msg_iov = &iov;
 738         msg.msg_iovlen = 1;
 739
 740         flags = MSG_PEEK;
 741
 742 retry:
 743         iov.iov_len = network->netlink_buf_size;
 744         iov.iov_base = network->netlink_buf;
 745
 746         rc = recvmsg(network->netlink_sd, &msg, flags);
 747
 748         if (rc < 0) {
 749                 perror("netlink recv header");
 750                 return -1;
 751         }
 752
 753         len = rc;
 754
 755         /* if the netlink message was larger than our buffer, realloc
 756          * before reading again */
 757         if (len > network->netlink_buf_size || msg.msg_flags & MSG_TRUNC) {
 758                 network->netlink_buf_size *= 2;
 759                 network->netlink_buf = talloc_realloc(network,
 760                                         network->netlink_buf,
 761                                         char *,
 762                                         network->netlink_buf_size);
 763                 goto retry;
 764         }
 765
 766         /* otherwise, we're good to read the entire message without PEEK */
 767         if (flags == MSG_PEEK) {
 768                 flags = 0;
 769                 goto retry;
 770         }
 771
 772         for_each_nlmsg(network->netlink_buf, nlmsg, len)
 773                 network_handle_nlmsg(network, nlmsg);
 774
 775         return 0;
 776 }
 777
 778 static void network_init_dns(struct network *network)
 779 {
 780         const struct config *config;
 781         unsigned int i;
 782         int rc, len;
 783         bool modified;
 784         char *buf;
 785
 786         if (network->dry_run)
 787                 return;
 788
 789         config = config_get();
 790         if (!config || !config->network.n_dns_servers)
 791                 return;
 792
 793         rc = read_file(network, "/etc/resolv.conf", &buf, &len);
 794
 795         if (rc) {
 796                 buf = talloc_strdup(network, "");
 797                 len = 0;
 798         }
 799
 800         modified = false;
 801
 802         for (i = 0; i < config->network.n_dns_servers; i++) {
 803                 int dns_conf_len;
 804                 char *dns_conf;
 805
 806                 dns_conf = talloc_asprintf(network, "nameserver %s\n",
 807                                 config->network.dns_servers[i]);
 808
 809                 if (strstr(buf, dns_conf)) {
 810                         talloc_free(dns_conf);
 811                         continue;
 812                 }
 813
 814                 dns_conf_len = strlen(dns_conf);
 815                 buf = talloc_realloc(network, buf, char, len + dns_conf_len + 1);
 816                 memcpy(buf + len, dns_conf, dns_conf_len);
 817                 len += dns_conf_len;
 818                 buf[len] = '\0';
 819                 modified = true;
 820
 821                 talloc_free(dns_conf);
 822         }
 823
 824         if (modified) {
 825                 rc = replace_file("/etc/resolv.conf", buf, len);
 826                 if (rc)
 827                         pb_log("error replacing resolv.conf: %s\n",
 828                                         strerror(errno));
 829         }
 830
 831         talloc_free(buf);
 832 }
 833
 834 struct network *network_init(struct device_handler *handler,
 835                 struct waitset *waitset, bool dry_run)
 836 {
 837         struct network *network;
 838         int rc;
 839
 840         network = talloc(handler, struct network);
 841         list_init(&network->interfaces);
 842         network->handler = handler;
 843         network->dry_run = dry_run;
 844         network->manual_config = config_get()->network.n_interfaces != 0;
 845
 846         network_init_dns(network);
 847
 848         rc = network_init_netlink(network);
 849         if (rc)
 850                 goto err;
 851
 852         network->waiter = waiter_register_io(waitset, network->netlink_sd,
 853                         WAIT_IN, network_netlink_process, network);
 854
 855         if (!network->waiter)
 856                 goto err;
 857
 858         rc = network_send_link_query(network);
 859         if (rc)
 860                 goto err;
 861
 862         return network;
 863
 864 err:
 865         network_shutdown(network);
 866         return NULL;
 867 }
 868
 869 int network_shutdown(struct network *network)
 870 {
 871         struct interface *interface;
 872
 873         if (network->waiter)
 874                 waiter_remove(network->waiter);
 875
 876         list_for_each_entry(&network->interfaces, interface, list) {
 877                 if (interface->state == IFSTATE_IGNORED)
 878                         continue;
 879                 if (!strcmp(interface->name, "lo"))
 880                         continue;
 881                 interface_down(interface);
 882         }
 883
 884         close(network->netlink_sd);
 885         talloc_free(network);
 886         return 0;
 887 }