interface.c

   1 /*
   2  * Copyright (C) 2014 John Crispin <blogic@openwrt.org>
   3  * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #define _GNU_SOURCE
  16 #include <sys/socket.h>
  17 #include <sys/ioctl.h>
  18 #include <sys/types.h>
  19 #include <sys/stat.h>
  20 #include <sys/utsname.h>
  21 #include <net/if.h>
  22 #include <netinet/in.h>
  23 #include <arpa/inet.h>
  24 #include <sys/types.h>
  25
  26 #include <ifaddrs.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <unistd.h>
  30 #include <stdio.h>
  31 #include <errno.h>
  32
  33 #include <libubox/usock.h>
  34 #include <libubox/uloop.h>
  35 #include <libubox/avl-cmp.h>
  36 #include <libubox/utils.h>
  37 #include "interface.h"
  38 #include "util.h"
  39 #include "dns.h"
  40 #include "announce.h"
  41
  42 static int
  43 interface_send_packet4(struct interface *iface, struct iovec *iov, int iov_len)
  44 {
  45         static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in_pktinfo)) / sizeof(size_t)) + 1];
  46         static struct sockaddr_in a;
  47         static struct msghdr m = {
  48                 .msg_name = (struct sockaddr *) &a,
  49                 .msg_namelen = sizeof(a),
  50                 .msg_control = cmsg_data,
  51                 .msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo)),
  52         };
  53         struct in_pktinfo *pkti;
  54         struct cmsghdr *cmsg;
  55         int fd = iface->fd.fd;
  56
  57         a.sin_family = AF_INET;
  58         a.sin_port = htons(MCAST_PORT);
  59         m.msg_iov = iov;
  60         m.msg_iovlen = iov_len;
  61
  62         memset(cmsg_data, 0, sizeof(cmsg_data));
  63         cmsg = CMSG_FIRSTHDR(&m);
  64         cmsg->cmsg_len = m.msg_controllen;
  65         cmsg->cmsg_level = IPPROTO_IP;
  66         cmsg->cmsg_type = IP_PKTINFO;
  67
  68         pkti = (struct in_pktinfo*) CMSG_DATA(cmsg);
  69         pkti->ipi_ifindex = iface->ifindex;
  70
  71         a.sin_addr.s_addr = inet_addr(MCAST_ADDR);
  72
  73         return sendmsg(fd, &m, 0);
  74 }
  75
  76 static int
  77 interface_send_packet6(struct interface *iface, struct iovec *iov, int iov_len)
  78 {
  79         static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in6_pktinfo)) / sizeof(size_t)) + 1];
  80         static struct sockaddr_in6 a;
  81         static struct msghdr m = {
  82                 .msg_name = (struct sockaddr *) &a,
  83                 .msg_namelen = sizeof(a),
  84                 .msg_control = cmsg_data,
  85                 .msg_controllen = CMSG_LEN(sizeof(struct in6_pktinfo)),
  86         };
  87         struct in6_pktinfo *pkti;
  88         struct cmsghdr *cmsg;
  89         int fd = iface->fd.fd;
  90
  91         a.sin6_family = AF_INET6;
  92         a.sin6_port = htons(MCAST_PORT);
  93         m.msg_iov = iov;
  94         m.msg_iovlen = iov_len;
  95
  96         memset(cmsg_data, 0, sizeof(cmsg_data));
  97         cmsg = CMSG_FIRSTHDR(&m);
  98         cmsg->cmsg_len = m.msg_controllen;
  99         cmsg->cmsg_level = IPPROTO_IPV6;
 100         cmsg->cmsg_type = IPV6_PKTINFO;
 101
 102         pkti = (struct in6_pktinfo*) CMSG_DATA(cmsg);
 103         pkti->ipi6_ifindex = iface->ifindex;
 104
 105         inet_pton(AF_INET6, MCAST_ADDR6, &a.sin6_addr);
 106
 107         return sendmsg(fd, &m, 0);
 108 }
 109
 110 int
 111 interface_send_packet(struct interface *iface, struct iovec *iov, int iov_len)
 112 {
 113         if (debug > 1) {
 114                 fprintf(stderr, "TX ipv%d: %s\n", iface->v6 * 2 + 4, iface->name);
 115                 fprintf(stderr, "  multicast: %d\n", iface->multicast);
 116         }
 117
 118         if (iface->v6)
 119                 return interface_send_packet6(iface, iov, iov_len);
 120
 121         return interface_send_packet4(iface, iov, iov_len);
 122 }
 123
 124 static void interface_close(struct interface *iface)
 125 {
 126         if (iface->fd.fd < 0)
 127                 return;
 128
 129         announce_free(iface);
 130         uloop_fd_delete(&iface->fd);
 131         close(iface->fd.fd);
 132         iface->fd.fd = -1;
 133 }
 134
 135 static void interface_free(struct interface *iface)
 136 {
 137         interface_close(iface);
 138         free(iface);
 139 }
 140
 141 static void
 142 read_socket4(struct uloop_fd *u, unsigned int events)
 143 {
 144         struct interface *iface = container_of(u, struct interface, fd);
 145         static uint8_t buffer[8 * 1024];
 146         struct iovec iov[1];
 147         char cmsg[CMSG_SPACE(sizeof(struct in_pktinfo)) + CMSG_SPACE(sizeof(int)) + 1];
 148         struct cmsghdr *cmsgptr;
 149         struct msghdr msg;
 150         socklen_t len;
 151         struct sockaddr_in from;
 152         int flags = 0, ifindex = -1;
 153         uint8_t ttl = 0;
 154         struct in_pktinfo *inp = NULL;
 155
 156         if (u->eof) {
 157                 interface_close(iface);
 158                 uloop_timeout_set(&iface->reconnect, 1000);
 159                 return;
 160         }
 161
 162         iov[0].iov_base = buffer;
 163         iov[0].iov_len = sizeof(buffer);
 164
 165         memset(&msg, 0, sizeof(msg));
 166         msg.msg_name = (struct sockaddr *) &from;
 167         msg.msg_namelen = sizeof(struct sockaddr_in);
 168         msg.msg_iov = iov;
 169         msg.msg_iovlen = 1;
 170         msg.msg_control = &cmsg;
 171         msg.msg_controllen = sizeof(cmsg);
 172
 173         len = recvmsg(u->fd, &msg, flags);
 174         if (len == -1) {
 175                 perror("read failed");
 176                 return;
 177         }
 178         for (cmsgptr = CMSG_FIRSTHDR(&msg); cmsgptr != NULL; cmsgptr = CMSG_NXTHDR(&msg, cmsgptr)) {
 179                 void *c = CMSG_DATA(cmsgptr);
 180
 181                 switch (cmsgptr->cmsg_type) {
 182                 case IP_PKTINFO:
 183                         inp = ((struct in_pktinfo *) c);
 184                         break;
 185
 186                 case IP_TTL:
 187                         ttl = (uint8_t) *((int *) c);
 188                         break;
 189
 190                 default:
 191                         fprintf(stderr, "unknown cmsg %x\n", cmsgptr->cmsg_type);
 192                         return;
 193                 }
 194         }
 195
 196         if (ttl != 255)
 197                 return;
 198
 199         if (debug > 1) {
 200                 char buf[256];
 201
 202                 fprintf(stderr, "RX ipv4: %s\n", iface->name);
 203                 fprintf(stderr, "  multicast: %d\n", iface->multicast);
 204                 inet_ntop(AF_INET, &from.sin_addr, buf, 256);
 205                 fprintf(stderr, "  src %s:%d\n", buf, from.sin_port);
 206                 inet_ntop(AF_INET, &inp->ipi_spec_dst, buf, 256);
 207                 fprintf(stderr, "  dst %s\n", buf);
 208                 inet_ntop(AF_INET, &inp->ipi_addr, buf, 256);
 209                 fprintf(stderr, "  real %s\n", buf);
 210         }
 211
 212         if (inp->ipi_ifindex != iface->ifindex)
 213                 fprintf(stderr, "invalid iface index %d != %d\n", ifindex, iface->ifindex);
 214         else
 215                 dns_handle_packet(iface, buffer, len, 0);
 216 }
 217
 218 static void
 219 read_socket6(struct uloop_fd *u, unsigned int events)
 220 {
 221         struct interface *iface = container_of(u, struct interface, fd);
 222         static uint8_t buffer[8 * 1024];
 223         struct iovec iov[1];
 224         char cmsg6[CMSG_SPACE(sizeof(struct in6_pktinfo)) + CMSG_SPACE(sizeof(int)) + 1];
 225         struct cmsghdr *cmsgptr;
 226         struct msghdr msg;
 227         socklen_t len;
 228         struct sockaddr_in6 from;
 229         int flags = 0, ifindex = -1;
 230         int ttl = 0;
 231         struct in6_pktinfo *inp = NULL;
 232
 233         if (u->eof) {
 234                 interface_close(iface);
 235                 uloop_timeout_set(&iface->reconnect, 1000);
 236                 return;
 237         }
 238
 239         iov[0].iov_base = buffer;
 240         iov[0].iov_len = sizeof(buffer);
 241
 242         memset(&msg, 0, sizeof(msg));
 243         msg.msg_name = (struct sockaddr *) &from;
 244         msg.msg_namelen = sizeof(struct sockaddr_in6);
 245         msg.msg_iov = iov;
 246         msg.msg_iovlen = 1;
 247         msg.msg_control = &cmsg6;
 248         msg.msg_controllen = sizeof(cmsg6);
 249
 250         len = recvmsg(u->fd, &msg, flags);
 251         if (len == -1) {
 252                 perror("read failed");
 253                 return;
 254         }
 255         for (cmsgptr = CMSG_FIRSTHDR(&msg); cmsgptr != NULL; cmsgptr = CMSG_NXTHDR(&msg, cmsgptr)) {
 256                 void *c = CMSG_DATA(cmsgptr);
 257
 258                 switch (cmsgptr->cmsg_type) {
 259                 case IPV6_PKTINFO:
 260                         inp = ((struct in6_pktinfo *) c);
 261                         break;
 262
 263                 case IPV6_HOPLIMIT:
 264                         ttl = (uint8_t) *((int *) c);
 265                         break;
 266
 267                 default:
 268                         fprintf(stderr, "unknown cmsg %x\n", cmsgptr->cmsg_type);
 269                         return;
 270                 }
 271         }
 272
 273         if (ttl != 255)
 274                 return;
 275
 276         if (debug > 1) {
 277                 char buf[256];
 278
 279                 fprintf(stderr, "RX ipv6: %s\n", iface->name);
 280                 fprintf(stderr, "  multicast: %d\n", iface->multicast);
 281                 inet_ntop(AF_INET6, &from.sin6_addr, buf, 256);
 282                 fprintf(stderr, "  src %s:%d\n", buf, from.sin6_port);
 283                 inet_ntop(AF_INET6, &inp->ipi6_addr, buf, 256);
 284                 fprintf(stderr, "  dst %s\n", buf);
 285         }
 286
 287         if (inp->ipi6_ifindex != iface->ifindex)
 288                 fprintf(stderr, "invalid iface index %d != %d\n", ifindex, iface->ifindex);
 289         else
 290                 dns_handle_packet(iface, buffer, len, 0);
 291 }
 292
 293 static int
 294 interface_mcast_setup4(struct interface *iface)
 295 {
 296         struct ip_mreqn mreq;
 297         uint8_t ttl = 255;
 298         int no = 0;
 299         struct sockaddr_in sa = { 0 };
 300         int fd = iface->fd.fd;
 301
 302         sa.sin_family = AF_INET;
 303         sa.sin_port = htons(MCAST_PORT);
 304         inet_pton(AF_INET, MCAST_ADDR, &sa.sin_addr);
 305
 306         memset(&mreq, 0, sizeof(mreq));
 307         mreq.imr_address.s_addr = iface->v4_addr.s_addr;
 308         mreq.imr_multiaddr = sa.sin_addr;
 309         mreq.imr_ifindex = iface->ifindex;
 310
 311         if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
 312                 fprintf(stderr, "ioctl failed: IP_MULTICAST_TTL\n");
 313
 314         /* Some network drivers have issues with dropping membership of
 315          * mcast groups when the iface is down, but don't allow rejoining
 316          * when it comes back up. This is an ugly workaround
 317          * -- this was copied from avahi --
 318          */
 319         setsockopt(fd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mreq, sizeof(mreq));
 320
 321         if (setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0) {
 322                 fprintf(stderr, "failed to join multicast group: %s\n", strerror(errno));
 323                 close(fd);
 324                 fd = -1;
 325                 return -1;
 326         }
 327
 328         if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &no, sizeof(no)) < 0)
 329                 fprintf(stderr, "ioctl failed: IP_MULTICAST_LOOP\n");
 330
 331         return 0;
 332 }
 333
 334 static int
 335 interface_socket_setup6(struct interface *iface)
 336 {
 337         struct ipv6_mreq mreq;
 338         int ttl = 255;
 339         int no = 0;
 340         struct sockaddr_in6 sa = { 0 };
 341         int fd = iface->fd.fd;
 342
 343         sa.sin6_family = AF_INET6;
 344         sa.sin6_port = htons(MCAST_PORT);
 345         inet_pton(AF_INET6, MCAST_ADDR6, &sa.sin6_addr);
 346
 347         memset(&mreq, 0, sizeof(mreq));
 348         mreq.ipv6mr_multiaddr = sa.sin6_addr;
 349         mreq.ipv6mr_interface = iface->ifindex;
 350
 351         if (setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
 352                 fprintf(stderr, "ioctl failed: IPV6_MULTICAST_HOPS\n");
 353
 354         setsockopt(fd, IPPROTO_IPV6, IPV6_LEAVE_GROUP, &mreq, sizeof(mreq));
 355         if (setsockopt(fd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0) {
 356                 fprintf(stderr, "failed to join multicast group: %s\n", strerror(errno));
 357                 close(fd);
 358                 fd = -1;
 359                 return -1;
 360         }
 361
 362         if (setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &no, sizeof(no)) < 0)
 363                 fprintf(stderr, "ioctl failed: IPV6_MULTICAST_LOOP\n");
 364
 365         return 0;
 366 }
 367
 368 static void
 369 reconnect_socket4(struct uloop_timeout *timeout)
 370 {
 371         struct interface *iface = container_of(timeout, struct interface, reconnect);
 372         int yes = 1;
 373
 374         iface->fd.fd = usock(USOCK_UDP | USOCK_SERVER | USOCK_NONBLOCK | USOCK_IPV4ONLY,
 375                 (iface->multicast) ? (iface->mcast_addr) : (iface->v4_addrs), "5353");
 376         if (iface->fd.fd < 0) {
 377                 fprintf(stderr, "failed to add listener %s: %s\n", iface->mcast_addr, strerror(errno));
 378                 goto retry;
 379         }
 380
 381         if (setsockopt(iface->fd.fd, SOL_SOCKET, SO_BINDTODEVICE, iface->name, strlen(iface->name) < 0))
 382                 fprintf(stderr, "ioctl failed: SO_BINDTODEVICE\n");
 383
 384         if (setsockopt(iface->fd.fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0)
 385                 fprintf(stderr, "ioctl failed: SO_REUSEADDR\n");
 386
 387         if (setsockopt(iface->fd.fd, IPPROTO_IP, IP_RECVTTL, &yes, sizeof(yes)) < 0)
 388                 fprintf(stderr, "ioctl failed: IP_RECVTTL\n");
 389
 390         if (setsockopt(iface->fd.fd, IPPROTO_IP, IP_PKTINFO, &yes, sizeof(yes)) < 0)
 391                 fprintf(stderr, "ioctl failed: IP_PKTINFO\n");
 392
 393         if (iface->multicast && interface_mcast_setup4(iface)) {
 394                 iface->fd.fd = -1;
 395                 goto retry;
 396         }
 397
 398         uloop_fd_add(&iface->fd, ULOOP_READ);
 399         if (iface->multicast) {
 400                 dns_send_question(iface, "_services._dns-sd._udp.local", TYPE_PTR, 1);
 401                 announce_init(iface);
 402         }
 403
 404         return;
 405
 406 retry:
 407         uloop_timeout_set(timeout, 1000);
 408 }
 409
 410 static void
 411 reconnect_socket6(struct uloop_timeout *timeout)
 412 {
 413         struct interface *iface = container_of(timeout, struct interface, reconnect);
 414         char mcast_addr[128];
 415         int ttl = 255;
 416         int yes = 1;
 417
 418         snprintf(mcast_addr, sizeof(mcast_addr), "%s%%%s", (iface->multicast) ? (iface->mcast_addr) : (iface->v6_addrs), iface->name);
 419         iface->fd.fd = usock(USOCK_UDP | USOCK_SERVER | USOCK_NONBLOCK | USOCK_IPV6ONLY, mcast_addr, "5353");
 420         if (iface->fd.fd < 0) {
 421                 fprintf(stderr, "failed to add listener %s: %s\n", mcast_addr, strerror(errno));
 422                 goto retry;
 423         }
 424
 425         if (setsockopt(iface->fd.fd, SOL_SOCKET, SO_BINDTODEVICE, iface->name, strlen(iface->name) < 0))
 426                 fprintf(stderr, "ioctl failed: SO_BINDTODEVICE\n");
 427
 428         if (setsockopt(iface->fd.fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl)) < 0)
 429                 fprintf(stderr, "ioctl failed: IPV6_UNICAST_HOPS\n");
 430
 431         if (setsockopt(iface->fd.fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &yes, sizeof(yes)) < 0)
 432                 fprintf(stderr, "ioctl failed: IPV6_RECVPKTINFO\n");
 433
 434         if (setsockopt(iface->fd.fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &yes, sizeof(yes)) < 0)
 435                 fprintf(stderr, "ioctl failed: IPV6_RECVHOPLIMIT\n");
 436
 437         if (setsockopt(iface->fd.fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0)
 438                 fprintf(stderr, "ioctl failed: SO_REUSEADDR\n");
 439
 440         if (iface->multicast && interface_socket_setup6(iface)) {
 441                 iface->fd.fd = -1;
 442                 goto retry;
 443         }
 444
 445         uloop_fd_add(&iface->fd, ULOOP_READ);
 446
 447         if (iface->multicast) {
 448                 dns_send_question(iface, "_services._dns-sd._udp.local", TYPE_PTR, 1);
 449                 announce_init(iface);
 450         }
 451
 452         return;
 453
 454 retry:
 455         uloop_timeout_set(timeout, 1000);
 456 }
 457
 458
 459 static void interface_start(struct interface *iface)
 460 {
 461         if (iface->v6) {
 462                 iface->fd.cb = read_socket6;
 463                 iface->reconnect.cb = reconnect_socket6;
 464         } else {
 465                 iface->fd.cb = read_socket4;
 466                 iface->reconnect.cb = reconnect_socket4;
 467         }
 468         uloop_timeout_set(&iface->reconnect, 100);
 469 }
 470
 471 static void
 472 iface_update_cb(struct vlist_tree *tree, struct vlist_node *node_new,
 473                 struct vlist_node *node_old)
 474 {
 475         struct interface *iface;
 476
 477         if (node_old) {
 478                 iface = container_of(node_old, struct interface, node);
 479                 interface_free(iface);
 480         }
 481
 482         if (node_new) {
 483                 iface = container_of(node_new, struct interface, node);
 484                 interface_start(iface);
 485         }
 486 }
 487
 488 static struct interface* _interface_add(const char *name, int multicast, int v6)
 489 {
 490         struct interface *iface;
 491         char *name_buf;
 492         char *id_buf;
 493
 494         iface = calloc_a(sizeof(*iface),
 495                 &name_buf, strlen(name) + 1,
 496                 &id_buf, strlen(name) + 5);
 497
 498         sprintf(id_buf, "%d_%d_%s", multicast, v6, name);
 499         iface->name = strcpy(name_buf, name);
 500         iface->id = id_buf;
 501         iface->ifindex = if_nametoindex(name);
 502         iface->fd.fd = -1;
 503         iface->multicast = multicast;
 504         iface->v6 = v6;
 505         if (v6)
 506                 iface->mcast_addr = MCAST_ADDR6;
 507         else
 508                 iface->mcast_addr = MCAST_ADDR;
 509
 510         if (iface->ifindex <= 0)
 511                 goto error;
 512
 513         vlist_add(&interfaces, &iface->node, iface->id);
 514         return iface;
 515
 516 error:
 517         free(iface);
 518         return NULL;
 519 }
 520
 521 int interface_add(const char *name)
 522 {
 523         struct interface *v4 = NULL, *v6 = NULL, *unicast;
 524         struct ifaddrs *ifap, *ifa;
 525
 526         getifaddrs(&ifap);
 527
 528         for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 529                 if (strcmp(ifa->ifa_name, name))
 530                         continue;
 531                 if (ifa->ifa_addr->sa_family == AF_INET && !v4) {
 532                         struct sockaddr_in *sa;
 533
 534                         if (cfg_proto && (cfg_proto != 4))
 535                                 continue;
 536
 537                         unicast = _interface_add(name, 0, 0);
 538                         if (!unicast)
 539                                 continue;
 540                         sa = (struct sockaddr_in *) ifa->ifa_addr;
 541                         memcpy(&unicast->v4_addr, &sa->sin_addr, sizeof(unicast->v4_addr));
 542                         inet_ntop(AF_INET, &sa->sin_addr, unicast->v4_addrs, sizeof(unicast->v4_addrs));
 543
 544                         v4 = _interface_add(name, 1, 0);
 545                         if (!v4)
 546                                 continue;
 547                         memcpy(&v4->v4_addr, &sa->sin_addr, sizeof(v4->v4_addr));
 548                         inet_ntop(AF_INET, &sa->sin_addr, v4->v4_addrs, sizeof(v4->v4_addrs));
 549
 550                         v4->peer = unicast;
 551                         unicast->peer = v4;
 552                 }
 553
 554                 if (ifa->ifa_addr->sa_family == AF_INET6 && !v6) {
 555                         uint8_t ll_prefix[] = {0xfe, 0x80 };
 556                         struct sockaddr_in6 *sa6;
 557
 558                         if (cfg_proto && (cfg_proto != 6))
 559                                 continue;
 560
 561                         sa6 = (struct sockaddr_in6 *) ifa->ifa_addr;
 562                         if (memcmp(&sa6->sin6_addr, &ll_prefix, 2))
 563                                 continue;
 564
 565                         unicast = _interface_add(name, 0, 1);
 566                         if (!unicast)
 567                                 continue;
 568                         memcpy(&unicast->v6_addr, &sa6->sin6_addr, sizeof(unicast->v6_addr));
 569                         inet_ntop(AF_INET6, &sa6->sin6_addr, unicast->v6_addrs, sizeof(unicast->v6_addrs));
 570
 571                         v6 = _interface_add(name, 1, 1);
 572                         if (!v6)
 573                                 continue;
 574                         memcpy(&v6->v6_addr, &sa6->sin6_addr, sizeof(v6->v6_addr));
 575                         inet_ntop(AF_INET6, &sa6->sin6_addr, v6->v6_addrs, sizeof(v6->v6_addrs));
 576
 577                         v6->peer = unicast;
 578                         unicast->peer = v6;
 579                 }
 580         }
 581
 582         freeifaddrs(ifap);
 583
 584         return !v4 && !v6;
 585 }
 586
 587 VLIST_TREE(interfaces, avl_strcmp, iface_update_cb, false, false);