remote.c

   1 /*
   2  *   This program is free software; you can redistribute it and/or modify
   3  *   it under the terms of the GNU General Public License as published by
   4  *   the Free Software Foundation; either version 2 of the License.
   5  *
   6  *   This program is distributed in the hope that it will be useful,
   7  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  *   GNU General Public License for more details.
  10  *
  11  *   You should have received a copy of the GNU General Public License
  12  *   along with this program; if not, write to the Free Software
  13  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
  14  *
  15  *   Copyright (C) 2020 embedd.ch
  16  *   Copyright (C) 2020 Felix Fietkau <nbd@nbd.name>
  17  *   Copyright (C) 2020 John Crispin <john@phrozen.org>
  18  */
  19
  20 #define _GNU_SOURCE
  21
  22 #include <sys/types.h>
  23 #include <sys/socket.h>
  24 #include <netinet/in.h>
  25 #include <net/if.h>
  26 #include <arpa/inet.h>
  27 #include <errno.h>
  28 #include <unistd.h>
  29
  30 #include <libubox/vlist.h>
  31 #include <libubox/avl-cmp.h>
  32 #include <libubox/usock.h>
  33 #include "usteer.h"
  34 #include "remote.h"
  35 #include "node.h"
  36
  37 static uint32_t local_id;
  38 static struct uloop_fd remote_fd;
  39 static struct uloop_timeout remote_timer;
  40 static struct uloop_timeout reload_timer;
  41
  42 static struct blob_buf buf;
  43 static uint32_t msg_seq;
  44
  45 struct interface {
  46         struct vlist_node node;
  47         int ifindex;
  48 };
  49
  50 static void
  51 interfaces_update_cb(struct vlist_tree *tree,
  52                      struct vlist_node *node_new,
  53                      struct vlist_node *node_old);
  54
  55 static int remote_host_cmp(const void *k1, const void *k2, void *ptr)
  56 {
  57         unsigned long v1 = (unsigned long) k1;
  58         unsigned long v2 = (unsigned long) k2;
  59
  60         return v2 - v1;
  61 }
  62
  63 static VLIST_TREE(interfaces, avl_strcmp, interfaces_update_cb, true, true);
  64 LIST_HEAD(remote_nodes);
  65 AVL_TREE(remote_hosts, remote_host_cmp, false, NULL);
  66
  67 static const char *
  68 interface_name(struct interface *iface)
  69 {
  70         return iface->node.avl.key;
  71 }
  72
  73 static void
  74 interface_check(struct interface *iface)
  75 {
  76         iface->ifindex = if_nametoindex(interface_name(iface));
  77         uloop_timeout_set(&reload_timer, 1);
  78 }
  79
  80 static void
  81 interface_init(struct interface *iface)
  82 {
  83         interface_check(iface);
  84 }
  85
  86 static void
  87 interface_free(struct interface *iface)
  88 {
  89         avl_delete(&interfaces.avl, &iface->node.avl);
  90         free(iface);
  91 }
  92
  93 static void
  94 interfaces_update_cb(struct vlist_tree *tree,
  95                      struct vlist_node *node_new,
  96                      struct vlist_node *node_old)
  97 {
  98         struct interface *iface;
  99
 100         if (node_new && node_old) {
 101                 iface = container_of(node_new, struct interface, node);
 102                 free(iface);
 103                 iface = container_of(node_old, struct interface, node);
 104                 interface_check(iface);
 105         } else if (node_old) {
 106                 iface = container_of(node_old, struct interface, node);
 107                 interface_free(iface);
 108         } else {
 109                 iface = container_of(node_new, struct interface, node);
 110                 interface_init(iface);
 111         }
 112 }
 113
 114 void usteer_interface_add(const char *name)
 115 {
 116         struct interface *iface;
 117         char *name_buf;
 118
 119         iface = calloc_a(sizeof(*iface), &name_buf, strlen(name) + 1);
 120         strcpy(name_buf, name);
 121         vlist_add(&interfaces, &iface->node, name_buf);
 122 }
 123
 124 void config_set_interfaces(struct blob_attr *data)
 125 {
 126         struct blob_attr *cur;
 127         int rem;
 128
 129         if (!data)
 130                 return;
 131
 132         if (!blobmsg_check_attr_list(data, BLOBMSG_TYPE_STRING))
 133                 return;
 134
 135         vlist_update(&interfaces);
 136         blobmsg_for_each_attr(cur, data, rem) {
 137                 usteer_interface_add(blobmsg_data(cur));
 138         }
 139         vlist_flush(&interfaces);
 140 }
 141
 142 void config_get_interfaces(struct blob_buf *buf)
 143 {
 144         struct interface *iface;
 145         void *c;
 146
 147         c = blobmsg_open_array(buf, "interfaces");
 148         vlist_for_each_element(&interfaces, iface, node) {
 149                 blobmsg_add_string(buf, NULL, interface_name(iface));
 150         }
 151         blobmsg_close_array(buf, c);
 152 }
 153
 154 static void
 155 interface_add_station(struct usteer_remote_node *node, struct blob_attr *data)
 156 {
 157         struct sta *sta;
 158         struct sta_info *si;
 159         struct apmsg_sta msg;
 160         bool create;
 161
 162         if (!parse_apmsg_sta(&msg, data)) {
 163                 MSG(DEBUG, "Cannot parse station in message\n");
 164                 return;
 165         }
 166
 167         if (msg.timeout <= 0) {
 168                 MSG(DEBUG, "Refuse to add an already expired station entry\n");
 169                 return;
 170         }
 171
 172         sta = usteer_sta_get(msg.addr, true);
 173         if (!sta)
 174                 return;
 175
 176         si = usteer_sta_info_get(sta, &node->node, &create);
 177         if (!si)
 178                 return;
 179
 180         si->connected = msg.connected;
 181         si->signal = msg.signal;
 182         si->seen = current_time - msg.seen;
 183         si->last_connected = current_time - msg.last_connected;
 184         usteer_sta_info_update_timeout(si, msg.timeout);
 185 }
 186
 187 static void
 188 remote_node_free(struct usteer_remote_node *node)
 189 {
 190         struct usteer_remote_host *host = node->host;
 191
 192         list_del(&node->list);
 193         list_del(&node->host_list);
 194         usteer_sta_node_cleanup(&node->node);
 195         free(node);
 196
 197         if (!list_empty(&host->nodes))
 198                 return;
 199
 200         avl_delete(&remote_hosts, &host->avl);
 201         free(host->addr);
 202         free(host);
 203 }
 204
 205 static struct usteer_remote_host *
 206 interface_get_host(const char *addr, unsigned long id)
 207 {
 208         struct usteer_remote_host *host;
 209
 210         host = avl_find_element(&remote_hosts, (void *)id, host, avl);
 211         if (host)
 212                 goto out;
 213
 214         host = calloc(1, sizeof(*host));
 215         host->avl.key = (void *)id;
 216         INIT_LIST_HEAD(&host->nodes);
 217         avl_insert(&remote_hosts, &host->avl);
 218
 219 out:
 220         if (host->addr && !strcmp(host->addr, addr))
 221                 return host;
 222
 223         free(host->addr);
 224         host->addr = strdup(addr);
 225
 226         return host;
 227 }
 228
 229 static struct usteer_remote_node *
 230 interface_get_node(struct usteer_remote_host *host, const char *name)
 231 {
 232         struct usteer_remote_node *node;
 233         int addr_len = strlen(host->addr);
 234         char *buf;
 235
 236         list_for_each_entry(node, &host->nodes, host_list)
 237                 if (!strcmp(node->name, name))
 238                         return node;
 239
 240         node = calloc_a(sizeof(*node), &buf, addr_len + 1 + strlen(name) + 1);
 241         node->node.type = NODE_TYPE_REMOTE;
 242
 243         sprintf(buf, "%s#%s", host->addr, name);
 244         node->node.avl.key = buf;
 245         node->name = buf + addr_len + 1;
 246         node->host = host;
 247         INIT_LIST_HEAD(&node->node.sta_info);
 248
 249         list_add_tail(&node->list, &remote_nodes);
 250         list_add_tail(&node->host_list, &host->nodes);
 251
 252         return node;
 253 }
 254
 255 static void
 256 interface_add_node(struct usteer_remote_host *host, struct blob_attr *data)
 257 {
 258         struct usteer_remote_node *node;
 259         struct apmsg_node msg;
 260         struct blob_attr *cur;
 261         int rem;
 262
 263         if (!parse_apmsg_node(&msg, data)) {
 264                 MSG(DEBUG, "Cannot parse node in message\n");
 265                 return;
 266         }
 267
 268         node = interface_get_node(host, msg.name);
 269         node->check = 0;
 270         node->node.freq = msg.freq;
 271         node->node.n_assoc = msg.n_assoc;
 272         node->node.max_assoc = msg.max_assoc;
 273         node->node.noise = msg.noise;
 274         node->node.load = msg.load;
 275
 276         memcpy(node->node.bssid, msg.bssid, sizeof(node->node.bssid));
 277
 278         snprintf(node->node.ssid, sizeof(node->node.ssid), "%s", msg.ssid);
 279         usteer_node_set_blob(&node->node.rrm_nr, msg.rrm_nr);
 280         usteer_node_set_blob(&node->node.node_info, msg.node_info);
 281
 282         blob_for_each_attr(cur, msg.stations, rem)
 283                 interface_add_station(node, cur);
 284 }
 285
 286 static void
 287 interface_recv_msg(struct interface *iface, char *addr_str, void *buf, int len)
 288 {
 289         struct usteer_remote_host *host;
 290         struct blob_attr *data = buf;
 291         struct apmsg msg;
 292         struct blob_attr *cur;
 293         int rem;
 294
 295         if (blob_pad_len(data) != len) {
 296                 MSG(DEBUG, "Invalid message length (header: %d, real: %d)\n", blob_pad_len(data), len);
 297                 return;
 298         }
 299
 300         if (!parse_apmsg(&msg, data)) {
 301                 MSG(DEBUG, "Missing fields in message\n");
 302                 return;
 303         }
 304
 305         if (msg.id == local_id)
 306                 return;
 307
 308         MSG(NETWORK, "Received message on %s (id=%08x->%08x seq=%d len=%d)\n",
 309                 interface_name(iface), msg.id, local_id, msg.seq, len);
 310
 311         host = interface_get_host(addr_str, msg.id);
 312         usteer_node_set_blob(&host->host_info, msg.host_info);
 313
 314         blob_for_each_attr(cur, msg.nodes, rem)
 315                 interface_add_node(host, cur);
 316 }
 317
 318 static struct interface *
 319 interface_find_by_ifindex(int index)
 320 {
 321         struct interface *iface;
 322
 323         vlist_for_each_element(&interfaces, iface, node) {
 324                 if (iface->ifindex == index)
 325                         return iface;
 326         }
 327
 328         return NULL;
 329 }
 330
 331 static void
 332 interface_recv_v4(struct uloop_fd *u, unsigned int events)
 333 {
 334         static char buf[APMGR_BUFLEN];
 335         static char cmsg_buf[( CMSG_SPACE(sizeof(struct in_pktinfo)) + sizeof(int)) + 1];
 336         static struct sockaddr_in sin;
 337         char addr_str[INET_ADDRSTRLEN];
 338         static struct iovec iov = {
 339                 .iov_base = buf,
 340                 .iov_len = sizeof(buf)
 341         };
 342         static struct msghdr msg = {
 343                 .msg_name = &sin,
 344                 .msg_namelen = sizeof(sin),
 345                 .msg_iov = &iov,
 346                 .msg_iovlen = 1,
 347                 .msg_control = cmsg_buf,
 348                 .msg_controllen = sizeof(cmsg_buf),
 349         };
 350         struct cmsghdr *cmsg;
 351         int len;
 352
 353         do {
 354                 struct in_pktinfo *pkti = NULL;
 355                 struct interface *iface;
 356
 357                 len = recvmsg(u->fd, &msg, 0);
 358                 if (len < 0) {
 359                         switch (errno) {
 360                         case EAGAIN:
 361                                 return;
 362                         case EINTR:
 363                                 continue;
 364                         default:
 365                                 perror("recvmsg");
 366                                 uloop_fd_delete(u);
 367                                 return;
 368                         }
 369                 }
 370
 371                 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 372                         if (cmsg->cmsg_type != IP_PKTINFO)
 373                                 continue;
 374
 375                         pkti = (struct in_pktinfo *) CMSG_DATA(cmsg);
 376                 }
 377
 378                 if (!pkti) {
 379                         MSG(DEBUG, "Received packet without ifindex\n");
 380                         continue;
 381                 }
 382
 383                 iface = interface_find_by_ifindex(pkti->ipi_ifindex);
 384                 if (!iface) {
 385                         MSG(DEBUG, "Received packet from unconfigured interface %d\n", pkti->ipi_ifindex);
 386                         continue;
 387                 }
 388
 389                 inet_ntop(AF_INET, &sin.sin_addr, addr_str, sizeof(addr_str));
 390
 391                 interface_recv_msg(iface, addr_str, buf, len);
 392         } while (1);
 393 }
 394
 395
 396 static void interface_recv_v6(struct uloop_fd *u, unsigned int events){
 397         static char buf[APMGR_BUFLEN];
 398         static char cmsg_buf[( CMSG_SPACE(sizeof(struct in6_pktinfo)) + sizeof(int)) + 1];
 399         static struct sockaddr_in6 sin;
 400         static struct iovec iov = {
 401                 .iov_base = buf,
 402                 .iov_len = sizeof(buf)
 403         };
 404         static struct msghdr msg = {
 405                 .msg_name = &sin,
 406                 .msg_namelen = sizeof(sin),
 407                 .msg_iov = &iov,
 408                 .msg_iovlen = 1,
 409                 .msg_control = cmsg_buf,
 410                 .msg_controllen = sizeof(cmsg_buf),
 411         };
 412         struct cmsghdr *cmsg;
 413         char addr_str[INET6_ADDRSTRLEN];
 414         int len;
 415
 416         do {
 417                 struct in6_pktinfo *pkti = NULL;
 418                 struct interface *iface;
 419
 420                 len = recvmsg(u->fd, &msg, 0);
 421                 if (len < 0) {
 422                         switch (errno) {
 423                         case EAGAIN:
 424                                 return;
 425                         case EINTR:
 426                                 continue;
 427                         default:
 428                                 perror("recvmsg");
 429                                 uloop_fd_delete(u);
 430                                 return;
 431                         }
 432                 }
 433
 434                 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 435                         if (cmsg->cmsg_type != IPV6_PKTINFO)
 436                                 continue;
 437
 438                         pkti = (struct in6_pktinfo *) CMSG_DATA(cmsg);
 439                 }
 440
 441                 if (!pkti) {
 442                         MSG(DEBUG, "Received packet without ifindex\n");
 443                         continue;
 444                 }
 445
 446                 iface = interface_find_by_ifindex(pkti->ipi6_ifindex);
 447                 if (!iface) {
 448                         MSG(DEBUG, "Received packet from unconfigured interface %d\n", pkti->ipi6_ifindex);
 449                         continue;
 450                 }
 451
 452                 inet_ntop(AF_INET6, &sin.sin6_addr, addr_str, sizeof(addr_str));
 453                 if (sin.sin6_addr.s6_addr[0] == 0) {
 454                         /* IPv4 mapped address. Ignore. */
 455                         continue;
 456                 }
 457
 458                 interface_recv_msg(iface, addr_str, buf, len);
 459         } while (1);
 460 }
 461
 462 static void interface_send_msg_v4(struct interface *iface, struct blob_attr *data)
 463 {
 464         static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in_pktinfo)) / sizeof(size_t)) + 1];
 465         static struct sockaddr_in a;
 466         static struct iovec iov;
 467         static struct msghdr m = {
 468                 .msg_name = (struct sockaddr *) &a,
 469                 .msg_namelen = sizeof(a),
 470                 .msg_iov = &iov,
 471                 .msg_iovlen = 1,
 472                 .msg_control = cmsg_data,
 473                 .msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo)),
 474         };
 475         struct in_pktinfo *pkti;
 476         struct cmsghdr *cmsg;
 477
 478         a.sin_family = AF_INET;
 479         a.sin_port = htons(APMGR_PORT);
 480         a.sin_addr.s_addr = ~0;
 481
 482         memset(cmsg_data, 0, sizeof(cmsg_data));
 483         cmsg = CMSG_FIRSTHDR(&m);
 484         cmsg->cmsg_len = m.msg_controllen;
 485         cmsg->cmsg_level = IPPROTO_IP;
 486         cmsg->cmsg_type = IP_PKTINFO;
 487
 488         pkti = (struct in_pktinfo *) CMSG_DATA(cmsg);
 489         pkti->ipi_ifindex = iface->ifindex;
 490
 491         iov.iov_base = data;
 492         iov.iov_len = blob_pad_len(data);
 493
 494         if (sendmsg(remote_fd.fd, &m, 0) < 0)
 495                 perror("sendmsg");
 496 }
 497
 498
 499 static void interface_send_msg_v6(struct interface *iface, struct blob_attr *data) {
 500         static struct sockaddr_in6 groupSock = {};
 501
 502         groupSock.sin6_family = AF_INET6;
 503         inet_pton(AF_INET6, APMGR_V6_MCAST_GROUP, &groupSock.sin6_addr);
 504         groupSock.sin6_port = htons(APMGR_PORT);
 505
 506         setsockopt(remote_fd.fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &iface->ifindex, sizeof(iface->ifindex));
 507
 508         if (sendto(remote_fd.fd, data, blob_pad_len(data), 0, (const struct sockaddr *)&groupSock, sizeof(groupSock)) < 0)
 509                 perror("sendmsg");
 510 }
 511
 512 static void interface_send_msg(struct interface *iface, struct blob_attr *data){
 513         if (config.ipv6) {
 514                 interface_send_msg_v6(iface, data);
 515         } else {
 516                 interface_send_msg_v4(iface, data);
 517         }
 518 }
 519
 520 static void usteer_send_sta_info(struct sta_info *sta)
 521 {
 522         int seen = current_time - sta->seen;
 523         int last_connected = !!sta->connected ? 0 : current_time - sta->last_connected;
 524         void *c;
 525
 526         c = blob_nest_start(&buf, 0);
 527         blob_put(&buf, APMSG_STA_ADDR, sta->sta->addr, 6);
 528         blob_put_int8(&buf, APMSG_STA_CONNECTED, !!sta->connected);
 529         blob_put_int32(&buf, APMSG_STA_SIGNAL, sta->signal);
 530         blob_put_int32(&buf, APMSG_STA_SEEN, seen);
 531         blob_put_int32(&buf, APMSG_STA_LAST_CONNECTED, last_connected);
 532         blob_put_int32(&buf, APMSG_STA_TIMEOUT, config.local_sta_timeout - seen);
 533         blob_nest_end(&buf, c);
 534 }
 535
 536 static void usteer_send_node(struct usteer_node *node, struct sta_info *sta)
 537 {
 538         void *c, *s, *r;
 539
 540         c = blob_nest_start(&buf, 0);
 541
 542         blob_put_string(&buf, APMSG_NODE_NAME, usteer_node_name(node));
 543         blob_put_string(&buf, APMSG_NODE_SSID, node->ssid);
 544         blob_put_int32(&buf, APMSG_NODE_FREQ, node->freq);
 545         blob_put_int32(&buf, APMSG_NODE_NOISE, node->noise);
 546         blob_put_int32(&buf, APMSG_NODE_LOAD, node->load);
 547         blob_put_int32(&buf, APMSG_NODE_N_ASSOC, node->n_assoc);
 548         blob_put_int32(&buf, APMSG_NODE_MAX_ASSOC, node->max_assoc);
 549         blob_put(&buf, APMSG_NODE_BSSID, node->bssid, sizeof(node->bssid));
 550         if (node->rrm_nr) {
 551                 r = blob_nest_start(&buf, APMSG_NODE_RRM_NR);
 552                 blobmsg_add_field(&buf, BLOBMSG_TYPE_ARRAY, "",
 553                                   blobmsg_data(node->rrm_nr),
 554                                   blobmsg_data_len(node->rrm_nr));
 555                 blob_nest_end(&buf, r);
 556         }
 557
 558         if (node->node_info)
 559                 blob_put(&buf, APMSG_NODE_NODE_INFO,
 560                          blob_data(node->node_info),
 561                          blob_len(node->node_info));
 562
 563         s = blob_nest_start(&buf, APMSG_NODE_STATIONS);
 564
 565         if (sta) {
 566                 usteer_send_sta_info(sta);
 567         } else {
 568                 list_for_each_entry(sta, &node->sta_info, node_list)
 569                         usteer_send_sta_info(sta);
 570         }
 571
 572         blob_nest_end(&buf, s);
 573
 574         blob_nest_end(&buf, c);
 575 }
 576
 577 static void
 578 usteer_check_timeout(void)
 579 {
 580         struct usteer_remote_node *node, *tmp;
 581         int timeout = config.remote_node_timeout;
 582
 583         list_for_each_entry_safe(node, tmp, &remote_nodes, list) {
 584                 if (node->check++ > timeout)
 585                         remote_node_free(node);
 586         }
 587 }
 588
 589 static void *
 590 usteer_update_init(void)
 591 {
 592         blob_buf_init(&buf, 0);
 593         blob_put_int32(&buf, APMSG_ID, local_id);
 594         blob_put_int32(&buf, APMSG_SEQ, ++msg_seq);
 595         if (host_info_blob)
 596                 blob_put(&buf, APMSG_HOST_INFO,
 597                          blob_data(host_info_blob),
 598                          blob_len(host_info_blob));
 599
 600         return blob_nest_start(&buf, APMSG_NODES);
 601 }
 602
 603 static void
 604 usteer_update_send(void *c)
 605 {
 606         struct interface *iface;
 607
 608         blob_nest_end(&buf, c);
 609
 610         vlist_for_each_element(&interfaces, iface, node)
 611                 interface_send_msg(iface, buf.head);
 612 }
 613
 614 void
 615 usteer_send_sta_update(struct sta_info *si)
 616 {
 617         void *c = usteer_update_init();
 618         usteer_send_node(si->node, si);
 619         usteer_update_send(c);
 620 }
 621
 622 static void
 623 usteer_send_update_timer(struct uloop_timeout *t)
 624 {
 625         struct usteer_node *node;
 626         void *c;
 627
 628         usteer_update_time();
 629         uloop_timeout_set(t, config.remote_update_interval);
 630
 631         if (!avl_is_empty(&local_nodes) || host_info_blob) {
 632                 c = usteer_update_init();
 633                 for_each_local_node(node)
 634                         usteer_send_node(node, NULL);
 635
 636                 usteer_update_send(c);
 637         }
 638         usteer_check_timeout();
 639 }
 640
 641 static int
 642 usteer_init_local_id(void)
 643 {
 644         FILE *f;
 645
 646         f = fopen("/dev/urandom", "r");
 647         if (!f) {
 648                 perror("fopen(/dev/urandom)");
 649                 return -1;
 650         }
 651
 652         if (fread(&local_id, sizeof(local_id), 1, f) < 1)
 653                 return -1;
 654
 655         fclose(f);
 656         return 0;
 657 }
 658
 659 static int usteer_create_v4_socket() {
 660         int yes = 1;
 661         int fd;
 662
 663         fd = usock(USOCK_UDP | USOCK_SERVER | USOCK_NONBLOCK |
 664                    USOCK_NUMERIC | USOCK_IPV4ONLY,
 665                    "0.0.0.0", APMGR_PORT_STR);
 666         if (fd < 0) {
 667                 perror("usock");
 668                 return - 1;
 669         }
 670
 671         if (setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &yes, sizeof(yes)) < 0)
 672                 perror("setsockopt(IP_PKTINFO)");
 673
 674         if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &yes, sizeof(yes)) < 0)
 675                 perror("setsockopt(SO_BROADCAST)");
 676
 677         return fd;
 678 }
 679
 680
 681 static int usteer_create_v6_socket() {
 682         struct interface *iface;
 683         struct ipv6_mreq group;
 684         int yes = 1;
 685         int fd;
 686
 687         fd = usock(USOCK_UDP | USOCK_SERVER | USOCK_NONBLOCK |
 688                    USOCK_NUMERIC | USOCK_IPV6ONLY,
 689                    "::", APMGR_PORT_STR);
 690         if (fd < 0) {
 691                 perror("usock");
 692                 return fd;
 693         }
 694
 695         if (!inet_pton(AF_INET6, APMGR_V6_MCAST_GROUP, &group.ipv6mr_multiaddr.s6_addr))
 696                 perror("inet_pton(AF_INET6)");
 697
 698         /* Membership has to be added for every interface we listen on. */
 699         vlist_for_each_element(&interfaces, iface, node) {
 700                 group.ipv6mr_interface = iface->ifindex;
 701                 if(setsockopt(fd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, (char *)&group, sizeof group) < 0)
 702                         perror("setsockopt(IPV6_ADD_MEMBERSHIP)");
 703         }
 704
 705         if (setsockopt(fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &yes, sizeof(yes)) < 0)
 706                 perror("setsockopt(IPV6_RECVPKTINFO)");
 707
 708         if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &yes, sizeof(yes)) < 0)
 709                 perror("setsockopt(SO_BROADCAST)");
 710
 711         return fd;
 712 }
 713
 714 static void usteer_reload_timer(struct uloop_timeout *t) {
 715         /* Remove uloop descriptor */
 716         if (remote_fd.fd && remote_fd.registered) {
 717                 uloop_fd_delete(&remote_fd);
 718                 close(remote_fd.fd);
 719         }
 720
 721         if (config.ipv6) {
 722                 remote_fd.fd = usteer_create_v6_socket();
 723                 remote_fd.cb = interface_recv_v6;
 724         } else {
 725                 remote_fd.fd = usteer_create_v4_socket();
 726                 remote_fd.cb = interface_recv_v4;
 727         }
 728
 729         if (remote_fd.fd < 0)
 730                 return;
 731
 732         uloop_fd_add(&remote_fd, ULOOP_READ);
 733 }
 734
 735 int usteer_interface_init(void)
 736 {
 737         if (usteer_init_local_id())
 738                 return -1;
 739
 740         remote_timer.cb = usteer_send_update_timer;
 741         remote_timer.cb(&remote_timer);
 742
 743         reload_timer.cb = usteer_reload_timer;
 744         reload_timer.cb(&reload_timer);
 745
 746         return 0;
 747 }