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