src/router.c

   1 /**
   2  * Copyright (C) 2012-2013 Steven Barth <steven@midlink.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License v2 as published by
   6  * the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #include <errno.h>
  16 #include <fcntl.h>
  17 #include <signal.h>
  18 #include <resolv.h>
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22 #include <stdbool.h>
  23 #include <net/route.h>
  24
  25 #include "router.h"
  26 #include "odhcpd.h"
  27
  28
  29 static void forward_router_solicitation(const struct interface *iface);
  30 static void forward_router_advertisement(uint8_t *data, size_t len);
  31
  32 static void handle_icmpv6(void *addr, void *data, size_t len,
  33                 struct interface *iface);
  34 static void send_router_advert(struct uloop_timeout *event);
  35 static void sigusr1_refresh(int signal);
  36
  37 static struct odhcpd_event router_event = {{.fd = -1}, handle_icmpv6};
  38
  39 static FILE *fp_route = NULL;
  40
  41
  42 int init_router(void)
  43 {
  44         // Open ICMPv6 socket
  45         int sock = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_ICMPV6);
  46         if (sock < 0 && errno != EAFNOSUPPORT) {
  47                 syslog(LOG_ERR, "Failed to open RAW-socket: %s", strerror(errno));
  48                 return -1;
  49         }
  50
  51         // Let the kernel compute our checksums
  52         int val = 2;
  53         setsockopt(sock, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val));
  54
  55         // This is required by RFC 4861
  56         val = 255;
  57         setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val, sizeof(val));
  58         setsockopt(sock, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &val, sizeof(val));
  59
  60         // We need to know the source interface
  61         val = 1;
  62         setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val, sizeof(val));
  63         setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &val, sizeof(val));
  64
  65         // Don't loop back
  66         val = 0;
  67         setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &val, sizeof(val));
  68
  69         // Filter ICMPv6 package types
  70         struct icmp6_filter filt;
  71         ICMP6_FILTER_SETBLOCKALL(&filt);
  72         ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
  73         ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt);
  74         setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, sizeof(filt));
  75
  76         // Register socket
  77         router_event.uloop.fd = sock;
  78         odhcpd_register(&router_event);
  79
  80         if (!(fp_route = fopen("/proc/net/ipv6_route", "r")))
  81                 syslog(LOG_ERR, "Failed to open routing table: %s",
  82                                 strerror(errno));
  83
  84         signal(SIGUSR1, sigusr1_refresh);
  85         return 0;
  86 }
  87
  88
  89 int setup_router_interface(struct interface *iface, bool enable)
  90 {
  91         struct ipv6_mreq all_nodes = {ALL_IPV6_NODES, iface->ifindex};
  92         struct ipv6_mreq all_routers = {ALL_IPV6_ROUTERS, iface->ifindex};
  93
  94         uloop_timeout_cancel(&iface->timer_rs);
  95         iface->timer_rs.cb = NULL;
  96
  97         setsockopt(router_event.uloop.fd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP,
  98                         &all_nodes, sizeof(all_nodes));
  99         setsockopt(router_event.uloop.fd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP,
 100                         &all_routers, sizeof(all_routers));
 101
 102         if (!enable) {
 103                 if (iface->ra)
 104                         send_router_advert(&iface->timer_rs);
 105         } else {
 106                 void *mreq = &all_routers;
 107
 108                 if (iface->ra == RELAYD_RELAY && iface->master) {
 109                         mreq = &all_nodes;
 110                         forward_router_solicitation(iface);
 111                 } else if (iface->ra == RELAYD_SERVER && !iface->master) {
 112                         iface->timer_rs.cb = send_router_advert;
 113                         send_router_advert(&iface->timer_rs);
 114                 }
 115
 116                 if (iface->ra == RELAYD_RELAY || (iface->ra == RELAYD_SERVER && !iface->master))
 117                         setsockopt(router_event.uloop.fd, IPPROTO_IPV6,
 118                                         IPV6_ADD_MEMBERSHIP, mreq, sizeof(all_nodes));
 119         }
 120         return 0;
 121 }
 122
 123
 124 // Signal handler to resend all RDs
 125 static void sigusr1_refresh(_unused int signal)
 126 {
 127         struct interface *iface;
 128         list_for_each_entry(iface, &interfaces, head)
 129                 if (iface->ra == RELAYD_SERVER && !iface->master)
 130                         uloop_timeout_set(&iface->timer_rs, 1000);
 131 }
 132
 133 static bool router_icmpv6_valid(struct sockaddr_in6 *source, uint8_t *data, size_t len)
 134 {
 135         struct icmp6_hdr *hdr = (struct icmp6_hdr *)data;
 136         struct icmpv6_opt *opt, *end = (struct icmpv6_opt*)&data[len];
 137
 138         /* Hoplimit is already checked in odhcpd_receive_packets */
 139         if (len < sizeof(*hdr) || hdr->icmp6_code)
 140                 return false;
 141
 142         switch (hdr->icmp6_type) {
 143         case ND_ROUTER_ADVERT:
 144                 if (!IN6_IS_ADDR_LINKLOCAL(&source->sin6_addr))
 145                         return false;
 146
 147                 opt = (struct icmpv6_opt *)((struct nd_router_advert *)data + 1);
 148                 break;
 149
 150         case ND_ROUTER_SOLICIT:
 151                 opt = (struct icmpv6_opt *)((struct nd_router_solicit *)data + 1);
 152                 break;
 153
 154         default:
 155                 return false;
 156         }
 157
 158         icmpv6_for_each_option(opt, opt, end)
 159                 if (opt->type == ND_OPT_SOURCE_LINKADDR &&
 160                                 IN6_IS_ADDR_UNSPECIFIED(&source->sin6_addr) &&
 161                                 hdr->icmp6_type == ND_ROUTER_SOLICIT)
 162                         return false;
 163
 164         // Check all options parsed successfully
 165         return opt == end;
 166 }
 167
 168 // Event handler for incoming ICMPv6 packets
 169 static void handle_icmpv6(void *addr, void *data, size_t len,
 170                 struct interface *iface)
 171 {
 172         struct icmp6_hdr *hdr = data;
 173
 174         if (!router_icmpv6_valid(addr, data, len))
 175                 return;
 176
 177         if ((iface->ra == RELAYD_SERVER && !iface->master)) { // Server mode
 178                 if (hdr->icmp6_type == ND_ROUTER_SOLICIT)
 179                         send_router_advert(&iface->timer_rs);
 180         } else if (iface->ra == RELAYD_RELAY) { // Relay mode
 181                 if (hdr->icmp6_type == ND_ROUTER_ADVERT && iface->master)
 182                         forward_router_advertisement(data, len);
 183                 else if (hdr->icmp6_type == ND_ROUTER_SOLICIT && !iface->master)
 184                         forward_router_solicitation(odhcpd_get_master_interface());
 185         }
 186 }
 187
 188
 189 // Detect whether a default route exists, also find the source prefixes
 190 static bool parse_routes(struct odhcpd_ipaddr *n, ssize_t len)
 191 {
 192         rewind(fp_route);
 193
 194         char line[512], ifname[16];
 195         bool found_default = false;
 196         struct odhcpd_ipaddr p = {IN6ADDR_ANY_INIT, 0, 0, false, 0, 0, 0};
 197         while (fgets(line, sizeof(line), fp_route)) {
 198                 uint32_t rflags;
 199                 if (sscanf(line, "00000000000000000000000000000000 00 "
 200                                 "%*s %*s %*s %*s %*s %*s %*s %15s", ifname) &&
 201                                 strcmp(ifname, "lo")) {
 202                         found_default = true;
 203                 } else if (sscanf(line, "%8" SCNx32 "%8" SCNx32 "%*8" SCNx32 "%*8" SCNx32 " %hhx %*s "
 204                                 "%*s 00000000000000000000000000000000 %*s %*s %*s %" SCNx32 " lo",
 205                                 &p.addr.s6_addr32[0], &p.addr.s6_addr32[1], &p.prefix, &rflags) &&
 206                                 p.prefix > 0 && (rflags & RTF_NONEXTHOP) && (rflags & RTF_REJECT)) {
 207                         // Find source prefixes by scanning through unreachable-routes
 208                         p.addr.s6_addr32[0] = htonl(p.addr.s6_addr32[0]);
 209                         p.addr.s6_addr32[1] = htonl(p.addr.s6_addr32[1]);
 210
 211                         for (ssize_t i = 0; i < len; ++i) {
 212                                 if (n[i].prefix <= 64 && n[i].prefix >= p.prefix &&
 213                                                 !odhcpd_bmemcmp(&p.addr, &n[i].addr, p.prefix)) {
 214                                         n[i].dprefix = p.prefix;
 215                                         break;
 216                                 }
 217                         }
 218
 219                 }
 220         }
 221
 222         return found_default;
 223 }
 224
 225
 226 // Router Advert server mode
 227 static void send_router_advert(struct uloop_timeout *event)
 228 {
 229         struct interface *iface =
 230                         container_of(event, struct interface, timer_rs);
 231
 232         int mtu = odhcpd_get_interface_mtu(iface->ifname);
 233         if (mtu < 0)
 234                 mtu = 1500;
 235
 236         struct {
 237                 struct nd_router_advert h;
 238                 struct icmpv6_opt lladdr;
 239                 struct nd_opt_mtu mtu;
 240                 struct nd_opt_prefix_info prefix[RELAYD_MAX_PREFIXES];
 241         } adv = {
 242                 .h = {{.icmp6_type = ND_ROUTER_ADVERT, .icmp6_code = 0}, 0, 0},
 243                 .lladdr = {ND_OPT_SOURCE_LINKADDR, 1, {0}},
 244                 .mtu = {ND_OPT_MTU, 1, 0, htonl(mtu)},
 245         };
 246
 247         if (iface->dhcpv6)
 248                 adv.h.nd_ra_flags_reserved = ND_RA_FLAG_OTHER;
 249
 250         if (iface->managed >= RELAYD_MANAGED_MFLAG)
 251                 adv.h.nd_ra_flags_reserved |= ND_RA_FLAG_MANAGED;
 252
 253         if (iface->route_preference < 0)
 254                 adv.h.nd_ra_flags_reserved |= ND_RA_PREF_LOW;
 255         else if (iface->route_preference > 0)
 256                 adv.h.nd_ra_flags_reserved |= ND_RA_PREF_HIGH;
 257         odhcpd_get_mac(iface, adv.lladdr.data);
 258
 259         // If not currently shutting down
 260         struct odhcpd_ipaddr addrs[RELAYD_MAX_PREFIXES];
 261         ssize_t ipcnt = 0;
 262         uint64_t maxpreferred = 0;
 263
 264         // If not shutdown
 265         if (event->cb) {
 266                 ipcnt = odhcpd_get_interface_addresses(iface->ifindex,
 267                                 addrs, ARRAY_SIZE(addrs));
 268
 269                 // Check default route
 270                 if (parse_routes(addrs, ipcnt) || iface->default_router > 1)
 271                         adv.h.nd_ra_router_lifetime =
 272                                         htons(3 * MaxRtrAdvInterval);
 273         }
 274
 275         // Construct Prefix Information options
 276         bool have_public = false;
 277         size_t cnt = 0;
 278
 279         struct in6_addr dns_pref = IN6ADDR_ANY_INIT, *dns_addr = &dns_pref;
 280         uint32_t dns_time = 0;
 281         size_t dns_cnt = 1;
 282
 283         for (ssize_t i = 0; i < ipcnt; ++i) {
 284                 struct odhcpd_ipaddr *addr = &addrs[i];
 285                 if (addr->prefix > 96 || addr->has_class)
 286                         continue; // Address not suitable
 287
 288                 if (addr->preferred > MaxPreferredTime)
 289                         addr->preferred = MaxPreferredTime;
 290
 291                 if (addr->valid > MaxValidTime)
 292                         addr->valid = MaxValidTime;
 293
 294                 struct nd_opt_prefix_info *p = NULL;
 295                 for (size_t i = 0; i < cnt; ++i) {
 296                         if (addr->prefix == adv.prefix[i].nd_opt_pi_prefix_len &&
 297                                         !odhcpd_bmemcmp(&adv.prefix[i].nd_opt_pi_prefix,
 298                                         &addr->addr, addr->prefix))
 299                                 p = &adv.prefix[i];
 300                 }
 301
 302                 if (!p) {
 303                         if (cnt >= ARRAY_SIZE(adv.prefix))
 304                                 break;
 305
 306                         p = &adv.prefix[cnt++];
 307                 }
 308
 309                 if ((addr->addr.s6_addr[0] & 0xfe) != 0xfc && addr->preferred > 0) {
 310                         have_public = true;
 311
 312                         if (maxpreferred < 1000 * addr->preferred)
 313                                 maxpreferred = 1000 * addr->preferred;
 314                 }
 315
 316                 odhcpd_bmemcpy(&p->nd_opt_pi_prefix, &addr->addr, addr->prefix);
 317                 p->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
 318                 p->nd_opt_pi_len = 4;
 319                 p->nd_opt_pi_prefix_len = (addr->prefix < 64) ? 64 : addr->prefix;
 320                 p->nd_opt_pi_flags_reserved = 0;
 321                 if (!iface->ra_not_onlink)
 322                         p->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_ONLINK;
 323                 if (iface->managed < RELAYD_MANAGED_NO_AFLAG && addr->prefix <= 64)
 324                         p->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_AUTO;
 325                 p->nd_opt_pi_valid_time = htonl(addr->valid);
 326                 p->nd_opt_pi_preferred_time = htonl(addr->preferred);
 327
 328                 if (addr->preferred > dns_time) {
 329                         dns_time = addr->preferred;
 330                         dns_pref = addr->addr;
 331                 }
 332         }
 333
 334         if (!have_public && !iface->default_router && adv.h.nd_ra_router_lifetime) {
 335                 syslog(LOG_WARNING, "A default route is present but there is no public prefix "
 336                                 "on %s thus we don't announce a default route!", iface->ifname);
 337                 adv.h.nd_ra_router_lifetime = 0;
 338         }
 339
 340         // DNS Recursive DNS
 341         if (iface->dns_cnt > 0) {
 342                 dns_addr = iface->dns;
 343                 dns_cnt = iface->dns_cnt;
 344                 dns_time = 2 * MaxRtrAdvInterval;
 345         }
 346
 347         if (!dns_addr || IN6_IS_ADDR_UNSPECIFIED(dns_addr))
 348                 dns_cnt = 0;
 349
 350         struct {
 351                 uint8_t type;
 352                 uint8_t len;
 353                 uint8_t pad;
 354                 uint8_t pad2;
 355                 uint32_t lifetime;
 356         } dns = {ND_OPT_RECURSIVE_DNS, (1 + (2 * dns_cnt)), 0, 0, htonl(dns_time)};
 357
 358
 359
 360         // DNS Search options
 361         uint8_t search_buf[256], *search_domain = iface->search;
 362         size_t search_len = iface->search_len, search_padded = 0;
 363
 364         if (!search_domain && !res_init() && _res.dnsrch[0] && _res.dnsrch[0][0]) {
 365                 int len = dn_comp(_res.dnsrch[0], search_buf,
 366                                 sizeof(search_buf), NULL, NULL);
 367                 if (len > 0) {
 368                         search_domain = search_buf;
 369                         search_len = len;
 370                 }
 371         }
 372
 373         if (search_len > 0)
 374                 search_padded = ((search_len + 7) & (~7)) + 8;
 375
 376         struct {
 377                 uint8_t type;
 378                 uint8_t len;
 379                 uint8_t pad;
 380                 uint8_t pad2;
 381                 uint32_t lifetime;
 382                 uint8_t name[];
 383         } *search = alloca(sizeof(*search) + search_padded);
 384
 385         if (!search) {
 386                 syslog(LOG_ERR, "Alloca failed for dns search on interface %s", iface->ifname);
 387                 return;
 388         }
 389         search->type = ND_OPT_DNS_SEARCH;
 390         search->len = search_len ? ((sizeof(*search) + search_padded) / 8) : 0;
 391         search->pad = 0;
 392         search->pad2 = 0;
 393         search->lifetime = htonl(2 * MaxRtrAdvInterval);;
 394         memcpy(search->name, search_domain, search_len);
 395         memset(&search->name[search_len], 0, search_padded - search_len);
 396
 397
 398         size_t routes_cnt = 0;
 399         struct {
 400                 uint8_t type;
 401                 uint8_t len;
 402                 uint8_t prefix;
 403                 uint8_t flags;
 404                 uint32_t lifetime;
 405                 uint32_t addr[4];
 406         } routes[RELAYD_MAX_PREFIXES];
 407
 408         for (ssize_t i = 0; i < ipcnt; ++i) {
 409                 struct odhcpd_ipaddr *addr = &addrs[i];
 410                 if (addr->dprefix > 64 || addr->dprefix == 0) {
 411                         continue; // Address not suitable
 412                 } else if (addr->dprefix > 32) {
 413                         addr->addr.s6_addr32[1] &= htonl(~((1U << (64 - addr->dprefix)) - 1));
 414                 } else if (addr->dprefix <= 32) {
 415                         addr->addr.s6_addr32[0] &= htonl(~((1U << (32 - addr->dprefix)) - 1));
 416                         addr->addr.s6_addr32[1] = 0;
 417                 }
 418
 419                 routes[routes_cnt].type = ND_OPT_ROUTE_INFO;
 420                 routes[routes_cnt].len = sizeof(*routes) / 8;
 421                 routes[routes_cnt].prefix = addr->dprefix;
 422                 routes[routes_cnt].flags = 0;
 423                 if (iface->route_preference < 0)
 424                         routes[routes_cnt].flags |= ND_RA_PREF_LOW;
 425                 else if (iface->route_preference > 0)
 426                         routes[routes_cnt].flags |= ND_RA_PREF_HIGH;
 427                 routes[routes_cnt].lifetime = htonl(addr->valid);
 428                 routes[routes_cnt].addr[0] = addr->addr.s6_addr32[0];
 429                 routes[routes_cnt].addr[1] = addr->addr.s6_addr32[1];
 430                 routes[routes_cnt].addr[2] = 0;
 431                 routes[routes_cnt].addr[3] = 0;
 432
 433                 ++routes_cnt;
 434         }
 435
 436
 437         struct iovec iov[] = {{&adv, (uint8_t*)&adv.prefix[cnt] - (uint8_t*)&adv},
 438                         {&routes, routes_cnt * sizeof(*routes)},
 439                         {&dns, (dns_cnt) ? sizeof(dns) : 0},
 440                         {dns_addr, dns_cnt * sizeof(*dns_addr)},
 441                         {search, search->len * 8}};
 442         struct sockaddr_in6 all_nodes = {AF_INET6, 0, 0, ALL_IPV6_NODES, 0};
 443         odhcpd_send(router_event.uloop.fd,
 444                         &all_nodes, iov, ARRAY_SIZE(iov), iface);
 445
 446         // Rearm timer if not shut down
 447         if (event->cb) {
 448                 uint32_t maxinterval = MaxRtrAdvInterval * 1000;
 449                 uint32_t mininterval = MinRtrAdvInterval * 1000;
 450
 451                 if (maxpreferred > 0 && maxinterval > maxpreferred / 2) {
 452                         maxinterval = maxpreferred / 2;
 453                         if (maxinterval < 4000)
 454                                 maxinterval = 4000;
 455
 456                         if (maxinterval >= 9000)
 457                                 mininterval = maxinterval / 3;
 458                         else
 459                                 mininterval = (maxinterval * 3) / 4;
 460                 }
 461
 462                 int msecs;
 463                 odhcpd_urandom(&msecs, sizeof(msecs));
 464                 msecs = (labs(msecs) % (maxinterval - mininterval)) + mininterval;
 465                 uloop_timeout_set(&iface->timer_rs, msecs);
 466         }
 467 }
 468
 469
 470 // Forward router solicitation
 471 static void forward_router_solicitation(const struct interface *iface)
 472 {
 473         if (!iface)
 474                 return;
 475
 476         struct icmp6_hdr rs = {ND_ROUTER_SOLICIT, 0, 0, {{0}}};
 477         struct iovec iov = {&rs, sizeof(rs)};
 478         struct sockaddr_in6 all_routers =
 479                 {AF_INET6, 0, 0, ALL_IPV6_ROUTERS, iface->ifindex};
 480
 481         syslog(LOG_NOTICE, "Sending RS to %s", iface->ifname);
 482         odhcpd_send(router_event.uloop.fd, &all_routers, &iov, 1, iface);
 483 }
 484
 485
 486 // Handler for incoming router solicitations on slave interfaces
 487 static void forward_router_advertisement(uint8_t *data, size_t len)
 488 {
 489         struct nd_router_advert *adv = (struct nd_router_advert *)data;
 490
 491         // Rewrite options
 492         uint8_t *end = data + len;
 493         uint8_t *mac_ptr = NULL;
 494         struct in6_addr *dns_ptr = NULL;
 495         size_t dns_count = 0;
 496
 497         struct icmpv6_opt *opt;
 498         icmpv6_for_each_option(opt, &adv[1], end) {
 499                 if (opt->type == ND_OPT_SOURCE_LINKADDR) {
 500                         // Store address of source MAC-address
 501                         mac_ptr = opt->data;
 502                 } else if (opt->type == ND_OPT_RECURSIVE_DNS && opt->len > 1) {
 503                         // Check if we have to rewrite DNS
 504                         dns_ptr = (struct in6_addr*)&opt->data[6];
 505                         dns_count = (opt->len - 1) / 2;
 506                 }
 507         }
 508
 509         syslog(LOG_NOTICE, "Got a RA");
 510
 511         // Indicate a proxy, however we don't follow the rest of RFC 4389 yet
 512         adv->nd_ra_flags_reserved |= ND_RA_FLAG_PROXY;
 513
 514         // Forward advertisement to all slave interfaces
 515         struct sockaddr_in6 all_nodes = {AF_INET6, 0, 0, ALL_IPV6_NODES, 0};
 516         struct iovec iov = {data, len};
 517
 518         struct odhcpd_ipaddr addr;
 519         struct interface *iface;
 520         list_for_each_entry(iface, &interfaces, head) {
 521                 if (iface->ra != RELAYD_RELAY || iface->master)
 522                         continue;
 523
 524                 // Fixup source hardware address option
 525                 if (mac_ptr)
 526                         odhcpd_get_mac(iface, mac_ptr);
 527
 528                 // If we have to rewrite DNS entries
 529                 if (iface->always_rewrite_dns && dns_ptr && dns_count > 0) {
 530                         const struct in6_addr *rewrite = iface->dns;
 531                         size_t rewrite_cnt = iface->dns_cnt;
 532
 533                         if (rewrite_cnt == 0) {
 534                                 if (odhcpd_get_interface_addresses(iface->ifindex, &addr, 1) < 1)
 535                                         continue; // Unable to comply
 536
 537                                 rewrite = &addr.addr;
 538                                 rewrite_cnt = 1;
 539                         }
 540
 541                         // Copy over any other addresses
 542                         for (size_t i = 0; i < dns_count; ++i) {
 543                                 size_t j = (i < rewrite_cnt) ? i : rewrite_cnt - 1;
 544                                 dns_ptr[i] = rewrite[j];
 545                         }
 546                 }
 547
 548                 odhcpd_send(router_event.uloop.fd, &all_nodes, &iov, 1, iface);
 549         }
 550 }