src/dhcpv6.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 <time.h>
  16 #include <fcntl.h>
  17 #include <errno.h>
  18 #include <stdlib.h>
  19 #include <signal.h>
  20 #include <limits.h>
  21 #include <resolv.h>
  22 #include <string.h>
  23 #include <unistd.h>
  24 #include <syslog.h>
  25 #include <stdbool.h>
  26 #include <sys/time.h>
  27 #include <sys/ioctl.h>
  28 #include <sys/socket.h>
  29 #include <netinet/in.h>
  30
  31 #include <net/if.h>
  32 #include <net/ethernet.h>
  33
  34 #include "odhcp6c.h"
  35 #include "md5.h"
  36
  37
  38 #define ALL_DHCPV6_RELAYS {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
  39                 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x02}}}
  40 #define DHCPV6_CLIENT_PORT 546
  41 #define DHCPV6_SERVER_PORT 547
  42 #define DHCPV6_DUID_LLADDR 3
  43 #define DHCPV6_REQ_DELAY 1
  44
  45
  46 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
  47                 const uint8_t transaction[3], enum dhcpv6_msg type,
  48                 const struct in6_addr *daddr);
  49
  50 static int dhcpv6_parse_ia(void *opt, void *end);
  51
  52 static int dhcpv6_calc_refresh_timers(void);
  53 static void dhcpv6_handle_status_code(_unused const enum dhcpv6_msg orig,
  54                 const uint16_t code, const void *status_msg, const int len,
  55                 int *ret);
  56 static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig,
  57                 const struct dhcpv6_ia_hdr *ia_hdr, const uint16_t code,
  58                 const void *status_msg, const int len,
  59                 bool handled_status_codes[_DHCPV6_Status_Max],
  60                 int *ret);
  61
  62 static reply_handler dhcpv6_handle_reply;
  63 static reply_handler dhcpv6_handle_advert;
  64 static reply_handler dhcpv6_handle_rebind_reply;
  65 static reply_handler dhcpv6_handle_reconfigure;
  66 static int dhcpv6_commit_advert(void);
  67
  68
  69
  70 // RFC 3315 - 5.5 Timeout and Delay values
  71 static struct dhcpv6_retx dhcpv6_retx[_DHCPV6_MSG_MAX] = {
  72         [DHCPV6_MSG_UNKNOWN] = {false, 1, 120, 0, "<POLL>",
  73                         dhcpv6_handle_reconfigure, NULL},
  74         [DHCPV6_MSG_SOLICIT] = {true, 1, 3600, 0, "SOLICIT",
  75                         dhcpv6_handle_advert, dhcpv6_commit_advert},
  76         [DHCPV6_MSG_REQUEST] = {true, 1, 30, 10, "REQUEST",
  77                         dhcpv6_handle_reply, NULL},
  78         [DHCPV6_MSG_RENEW] = {false, 10, 600, 0, "RENEW",
  79                         dhcpv6_handle_reply, NULL},
  80         [DHCPV6_MSG_REBIND] = {false, 10, 600, 0, "REBIND",
  81                         dhcpv6_handle_rebind_reply, NULL},
  82         [DHCPV6_MSG_RELEASE] = {false, 1, 0, 5, "RELEASE", NULL, NULL},
  83         [DHCPV6_MSG_DECLINE] = {false, 1, 0, 5, "DECLINE", NULL, NULL},
  84         [DHCPV6_MSG_INFO_REQ] = {true, 1, 120, 0, "INFOREQ",
  85                         dhcpv6_handle_reply, NULL},
  86 };
  87
  88
  89 // Sockets
  90 static int sock = -1;
  91 static int ifindex = -1;
  92 static int64_t t1 = 0, t2 = 0, t3 = 0;
  93
  94 // IA states
  95 static int request_prefix = -1;
  96 static enum odhcp6c_ia_mode na_mode = IA_MODE_NONE, pd_mode = IA_MODE_NONE;
  97 static bool accept_reconfig = false;
  98
  99 // Reconfigure key
 100 static uint8_t reconf_key[16];
 101
 102
 103 int init_dhcpv6(const char *ifname, int request_pd, int sol_timeout)
 104 {
 105         request_prefix = request_pd;
 106         dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = sol_timeout;
 107
 108         sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
 109         if (sock < 0)
 110                 return -1;
 111
 112         // Detect interface
 113         struct ifreq ifr;
 114         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
 115         if (ioctl(sock, SIOCGIFINDEX, &ifr) < 0)
 116                 return -1;
 117         ifindex = ifr.ifr_ifindex;
 118
 119         // Create client DUID
 120         size_t client_id_len;
 121         odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
 122         if (client_id_len == 0) {
 123                 uint8_t duid[14] = {0, DHCPV6_OPT_CLIENTID, 0, 10, 0,
 124                                 DHCPV6_DUID_LLADDR, 0, 1};
 125
 126                 if (ioctl(sock, SIOCGIFHWADDR, &ifr) >= 0)
 127                         memcpy(&duid[8], ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
 128
 129                 uint8_t zero[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
 130                 struct ifreq ifs[100], *ifp, *ifend;
 131                 struct ifconf ifc;
 132                 ifc.ifc_req = ifs;
 133                 ifc.ifc_len = sizeof(ifs);
 134
 135                 if (!memcmp(&duid[8], zero, ETHER_ADDR_LEN) &&
 136                                 ioctl(sock, SIOCGIFCONF, &ifc) >= 0) {
 137                         // If our interface doesn't have an address...
 138                         ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq));
 139                         for (ifp = ifc.ifc_req; ifp < ifend &&
 140                                         !memcmp(&duid[8], zero, ETHER_ADDR_LEN); ifp++) {
 141                                 memcpy(ifr.ifr_name, ifp->ifr_name,
 142                                                 sizeof(ifr.ifr_name));
 143                                 if (ioctl(sock, SIOCGIFHWADDR, &ifr) < 0)
 144                                         continue;
 145                                 memcpy(&duid[8], ifr.ifr_hwaddr.sa_data,
 146                                                 ETHER_ADDR_LEN);
 147                         }
 148                 }
 149
 150                 odhcp6c_add_state(STATE_CLIENT_ID, duid, sizeof(duid));
 151         }
 152
 153         // Create ORO
 154         uint16_t oro[] = {
 155                         htons(DHCPV6_OPT_SIP_SERVER_D),
 156                         htons(DHCPV6_OPT_SIP_SERVER_A),
 157                         htons(DHCPV6_OPT_DNS_SERVERS),
 158                         htons(DHCPV6_OPT_DNS_DOMAIN),
 159                         htons(DHCPV6_OPT_NTP_SERVER),
 160                         htons(DHCPV6_OPT_AFTR_NAME),
 161                         htons(DHCPV6_OPT_PD_EXCLUDE),
 162 #ifdef EXT_PREFIX_CLASS
 163                         htons(DHCPV6_OPT_PREFIX_CLASS),
 164 #endif
 165         };
 166         odhcp6c_add_state(STATE_ORO, oro, sizeof(oro));
 167
 168         do {
 169                 // Configure IPv6-options
 170                 int val = 1;
 171                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val)) < 0)
 172                         break;
 173                 if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) < 0)
 174                         break;
 175                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val, sizeof(val)) < 0)
 176                         break;
 177
 178                 val = 0;
 179                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &val, sizeof(val)) < 0)
 180                         break;
 181                 if (setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname)) < 0)
 182                         break;
 183
 184                 struct sockaddr_in6 client_addr = { .sin6_family = AF_INET6,
 185                         .sin6_port = htons(DHCPV6_CLIENT_PORT), .sin6_flowinfo = 0 };
 186                 if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr)) < 0)
 187                         break;
 188
 189                 return 0;
 190         } while (0);
 191
 192         return -1;
 193 }
 194
 195
 196 void dhcpv6_set_ia_mode(enum odhcp6c_ia_mode na, enum odhcp6c_ia_mode pd)
 197 {
 198         na_mode = na;
 199         pd_mode = pd;
 200 }
 201
 202
 203 static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
 204 {
 205         // Build FQDN
 206         char fqdn_buf[256];
 207         gethostname(fqdn_buf, sizeof(fqdn_buf));
 208         struct {
 209                 uint16_t type;
 210                 uint16_t len;
 211                 uint8_t flags;
 212                 uint8_t data[256];
 213         } fqdn;
 214         size_t fqdn_len = 5 + dn_comp(fqdn_buf, fqdn.data,
 215                         sizeof(fqdn.data), NULL, NULL);
 216         fqdn.type = htons(DHCPV6_OPT_FQDN);
 217         fqdn.len = htons(fqdn_len - 4);
 218         fqdn.flags = 0;
 219
 220
 221         // Build Client ID
 222         size_t cl_id_len;
 223         void *cl_id = odhcp6c_get_state(STATE_CLIENT_ID, &cl_id_len);
 224
 225         // Get Server ID
 226         size_t srv_id_len;
 227         void *srv_id = odhcp6c_get_state(STATE_SERVER_ID, &srv_id_len);
 228
 229         // Build IA_PDs
 230         size_t ia_pd_entries, ia_pd_len = 0;
 231         struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
 232         ia_pd_entries /= sizeof(*e);
 233         struct dhcpv6_ia_hdr hdr_ia_pd = {
 234                 htons(DHCPV6_OPT_IA_PD),
 235                 htons(sizeof(hdr_ia_pd) - 4),
 236                 1, 0, 0
 237         };
 238
 239
 240         uint8_t *ia_pd = alloca(ia_pd_entries * (sizeof(struct dhcpv6_ia_prefix) + 10));
 241         for (size_t i = 0; i < ia_pd_entries; ++i) {
 242                 uint8_t ex_len = 0;
 243                 if (e[i].priority > 0)
 244                         ex_len = ((e[i].priority - e[i].length - 1) / 8) + 6;
 245
 246                 struct dhcpv6_ia_prefix p = {
 247                         .type = htons(DHCPV6_OPT_IA_PREFIX),
 248                         .len = htons(sizeof(p) - 4U + ex_len),
 249                         .prefix = e[i].length,
 250                         .addr = e[i].target
 251                 };
 252
 253                 memcpy(ia_pd + ia_pd_len, &p, sizeof(p));
 254                 ia_pd_len += sizeof(p);
 255
 256                 if (ex_len) {
 257                         ia_pd[ia_pd_len++] = 0;
 258                         ia_pd[ia_pd_len++] = DHCPV6_OPT_PD_EXCLUDE;
 259                         ia_pd[ia_pd_len++] = 0;
 260                         ia_pd[ia_pd_len++] = ex_len - 4;
 261                         ia_pd[ia_pd_len++] = e[i].priority;
 262
 263                         uint32_t excl = ntohl(e[i].router.s6_addr32[1]);
 264                         excl >>= (64 - e[i].priority);
 265                         excl <<= 8 - ((e[i].priority - e[i].length) % 8);
 266
 267                         for (size_t i = ex_len - 5; i > 0; --i, excl >>= 8)
 268                                 ia_pd[ia_pd_len + i] = excl & 0xff;
 269                         ia_pd_len += ex_len - 5;
 270                 }
 271         }
 272
 273         struct dhcpv6_ia_prefix pref = {
 274                 .type = htons(DHCPV6_OPT_IA_PREFIX),
 275                 .len = htons(25), .prefix = request_prefix
 276         };
 277         if (request_prefix > 0 && ia_pd_len == 0 && type == DHCPV6_MSG_SOLICIT) {
 278                 ia_pd = (uint8_t*)&pref;
 279                 ia_pd_len = sizeof(pref);
 280         }
 281         hdr_ia_pd.len = htons(ntohs(hdr_ia_pd.len) + ia_pd_len);
 282
 283         // Build IA_NAs
 284         size_t ia_na_entries, ia_na_len = 0;
 285         void *ia_na = NULL;
 286         e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
 287         ia_na_entries /= sizeof(*e);
 288
 289         struct dhcpv6_ia_hdr hdr_ia_na = {
 290                 htons(DHCPV6_OPT_IA_NA),
 291                 htons(sizeof(hdr_ia_na) - 4),
 292                 1, 0, 0
 293         };
 294
 295         struct dhcpv6_ia_addr pa[ia_na_entries];
 296         for (size_t i = 0; i < ia_na_entries; ++i) {
 297                 pa[i].type = htons(DHCPV6_OPT_IA_ADDR);
 298                 pa[i].len = htons(sizeof(pa[i]) - 4U);
 299                 pa[i].addr = e[i].target;
 300                 pa[i].preferred = 0;
 301                 pa[i].valid = 0;
 302         }
 303
 304         ia_na = pa;
 305         ia_na_len = sizeof(pa);
 306         hdr_ia_na.len = htons(ntohs(hdr_ia_na.len) + ia_na_len);
 307
 308         // Reconfigure Accept
 309         struct {
 310                 uint16_t type;
 311                 uint16_t length;
 312         } reconf_accept = {htons(DHCPV6_OPT_RECONF_ACCEPT), 0};
 313
 314         // Request Information Refresh
 315         uint16_t oro_refresh = htons(DHCPV6_OPT_INFO_REFRESH);
 316
 317         // Prepare Header
 318         size_t oro_len;
 319         void *oro = odhcp6c_get_state(STATE_ORO, &oro_len);
 320         struct {
 321                 uint8_t type;
 322                 uint8_t trid[3];
 323                 uint16_t elapsed_type;
 324                 uint16_t elapsed_len;
 325                 uint16_t elapsed_value;
 326                 uint16_t oro_type;
 327                 uint16_t oro_len;
 328         } hdr = {
 329                 type, {trid[0], trid[1], trid[2]},
 330                 htons(DHCPV6_OPT_ELAPSED), htons(2),
 331                         htons((ecs > 0xffff) ? 0xffff : ecs),
 332                 htons(DHCPV6_OPT_ORO), htons(oro_len),
 333         };
 334
 335         struct iovec iov[] = {
 336                 {&hdr, sizeof(hdr)},
 337                 {oro, oro_len},
 338                 {&oro_refresh, 0},
 339                 {cl_id, cl_id_len},
 340                 {srv_id, srv_id_len},
 341                 {&reconf_accept, sizeof(reconf_accept)},
 342                 {&fqdn, fqdn_len},
 343                 {&hdr_ia_na, sizeof(hdr_ia_na)},
 344                 {ia_na, ia_na_len},
 345                 {&hdr_ia_pd, sizeof(hdr_ia_pd)},
 346                 {ia_pd, ia_pd_len},
 347         };
 348
 349         size_t cnt = ARRAY_SIZE(iov);
 350         if (type == DHCPV6_MSG_INFO_REQ) {
 351                 cnt = 5;
 352                 iov[2].iov_len = sizeof(oro_refresh);
 353                 hdr.oro_len = htons(oro_len + sizeof(oro_refresh));
 354         } else if (!request_prefix) {
 355                 cnt = 9;
 356         }
 357
 358         // Disable IAs if not used
 359         if (type != DHCPV6_MSG_SOLICIT) {
 360                 iov[5].iov_len = 0;
 361                 if (ia_na_len == 0)
 362                         iov[7].iov_len = 0;
 363                 if (ia_pd_len == 0)
 364                         iov[9].iov_len = 0;
 365         }
 366
 367         if (na_mode == IA_MODE_NONE)
 368                 iov[7].iov_len = 0;
 369
 370         struct sockaddr_in6 srv = {AF_INET6, htons(DHCPV6_SERVER_PORT),
 371                 0, ALL_DHCPV6_RELAYS, ifindex};
 372         struct msghdr msg = {&srv, sizeof(srv), iov, cnt, NULL, 0, 0};
 373
 374         sendmsg(sock, &msg, 0);
 375 }
 376
 377
 378 static int64_t dhcpv6_rand_delay(int64_t time)
 379 {
 380         int random;
 381         odhcp6c_random(&random, sizeof(random));
 382         return (time * ((int64_t)random % 1000LL)) / 10000LL;
 383 }
 384
 385
 386 int dhcpv6_request(enum dhcpv6_msg type)
 387 {
 388         uint8_t rc = 0;
 389         uint64_t timeout = UINT32_MAX;
 390         struct dhcpv6_retx *retx = &dhcpv6_retx[type];
 391
 392         if (retx->delay) {
 393                 struct timespec ts = {0, 0};
 394                 ts.tv_nsec = dhcpv6_rand_delay(10 * DHCPV6_REQ_DELAY);
 395                 nanosleep(&ts, NULL);
 396         }
 397
 398         if (type == DHCPV6_MSG_UNKNOWN)
 399                 timeout = t1;
 400         else if (type == DHCPV6_MSG_RENEW)
 401                 timeout = (t2 > t1) ? t2 - t1 : 0;
 402         else if (type == DHCPV6_MSG_REBIND)
 403                 timeout = (t3 > t2) ? t3 - t2 : 0;
 404
 405         if (timeout == 0)
 406                 return -1;
 407
 408         syslog(LOG_NOTICE, "Starting %s transaction (timeout %llus, max rc %d)",
 409                         retx->name, (unsigned long long)timeout, retx->max_rc);
 410
 411         uint64_t start = odhcp6c_get_milli_time(), round_start = start, elapsed;
 412
 413         // Generate transaction ID
 414         uint8_t trid[3] = {0, 0, 0};
 415         if (type != DHCPV6_MSG_UNKNOWN)
 416                 odhcp6c_random(trid, sizeof(trid));
 417         ssize_t len = -1;
 418         int64_t rto = 0;
 419
 420         do {
 421                 if (rto == 0) {
 422                         int64_t delay = dhcpv6_rand_delay(retx->init_timeo * 1000);
 423
 424                         // First RT MUST be strictly greater than IRT for solicit messages (RFC3313 17.1.2)
 425                         while (type == DHCPV6_MSG_SOLICIT && delay <= 0)
 426                                 delay = dhcpv6_rand_delay(retx->init_timeo * 1000);
 427
 428                         rto = (retx->init_timeo * 1000 + delay);
 429                 }
 430                 else
 431                         rto = (2 * rto + dhcpv6_rand_delay(rto));
 432
 433                 if (retx->max_timeo && (rto >= retx->max_timeo * 1000))
 434                         rto = retx->max_timeo * 1000 +
 435                                 dhcpv6_rand_delay(retx->max_timeo * 1000);
 436
 437                 // Calculate end for this round and elapsed time
 438                 uint64_t round_end = round_start + rto;
 439                 elapsed = round_start - start;
 440
 441                 // Don't wait too long
 442                 if (round_end - start > timeout * 1000)
 443                         round_end = timeout * 1000 + start;
 444
 445                 // Built and send package
 446                 if (type != DHCPV6_MSG_UNKNOWN) {
 447                         if (type != DHCPV6_MSG_SOLICIT)
 448                                 syslog(LOG_NOTICE, "Send %s message (elapsed %llums, rc %d)",
 449                                                 retx->name, (unsigned long long)elapsed, rc);
 450                         dhcpv6_send(type, trid, elapsed / 10);
 451                         rc++;
 452                 }
 453
 454                 // Receive rounds
 455                 for (; len < 0 && round_start < round_end;
 456                                 round_start = odhcp6c_get_milli_time()) {
 457                         uint8_t buf[1536], cmsg_buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
 458                         struct iovec iov = {buf, sizeof(buf)};
 459                         struct msghdr msg = {NULL, 0, &iov, 1,
 460                                         cmsg_buf, sizeof(cmsg_buf), 0};
 461                         struct in6_pktinfo *pktinfo = NULL;
 462
 463                         // Check for pending signal
 464                         if (odhcp6c_signal_process())
 465                                 return -1;
 466
 467                         // Set timeout for receiving
 468                         uint64_t t = round_end - round_start;
 469                         struct timeval timeout = {t / 1000, (t % 1000) * 1000};
 470                         setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO,
 471                                         &timeout, sizeof(timeout));
 472
 473                         // Receive cycle
 474                         len = recvmsg(sock, &msg, 0);
 475                         if (len < 0)
 476                                 continue;
 477
 478                         for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL;
 479                                 ch = CMSG_NXTHDR(&msg, ch)) {
 480                                 if (ch->cmsg_level == SOL_IPV6 &&
 481                                         ch->cmsg_type == IPV6_PKTINFO) {
 482                                         pktinfo = (struct in6_pktinfo *)CMSG_DATA(ch);
 483                                         break;
 484                                 }
 485                         }
 486
 487                         if (pktinfo == NULL) {
 488                                 len = -1;
 489                                 continue;
 490                         }
 491
 492                         if (!dhcpv6_response_is_valid(buf, len, trid,
 493                                                         type, &pktinfo->ipi6_addr)) {
 494                                 len = -1;
 495                                 continue;
 496                         }
 497
 498                         uint8_t *opt = &buf[4];
 499                         uint8_t *opt_end = opt + len - 4;
 500
 501                         round_start = odhcp6c_get_milli_time();
 502                         elapsed = round_start - start;
 503                         syslog(LOG_NOTICE, "Got a valid reply after "
 504                                         "%llums", (unsigned long long)elapsed);
 505
 506                         if (retx->handler_reply)
 507                                 len = retx->handler_reply(type, rc, opt, opt_end);
 508
 509                         if (len > 0 && round_end - round_start > 1000)
 510                                 round_end = 1000 + round_start;
 511                 }
 512
 513                 // Allow
 514                 if (retx->handler_finish)
 515                         len = retx->handler_finish();
 516         } while (len < 0 && ((elapsed / 1000 < timeout) && (!retx->max_rc || rc < retx->max_rc)));
 517
 518         return len;
 519 }
 520
 521 // Message validation checks according to RFC3315 chapter 15
 522 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
 523                 const uint8_t transaction[3], enum dhcpv6_msg type,
 524                 const struct in6_addr *daddr)
 525 {
 526         const struct dhcpv6_header *rep = buf;
 527         if (len < (ssize_t)sizeof(*rep) || memcmp(rep->tr_id,
 528                         transaction, sizeof(rep->tr_id)))
 529                 return false; // Invalid reply
 530
 531         if (type == DHCPV6_MSG_SOLICIT) {
 532                 if (rep->msg_type != DHCPV6_MSG_ADVERT &&
 533                                 rep->msg_type != DHCPV6_MSG_REPLY)
 534                         return false;
 535         } else if (type == DHCPV6_MSG_UNKNOWN) {
 536                 if (!accept_reconfig || rep->msg_type != DHCPV6_MSG_RECONF)
 537                         return false;
 538         } else if (rep->msg_type != DHCPV6_MSG_REPLY) {
 539                 return false;
 540         }
 541
 542         uint8_t *end = ((uint8_t*)buf) + len, *odata,
 543                 rcmsg = DHCPV6_MSG_UNKNOWN;
 544         uint16_t otype, olen;
 545         bool clientid_ok = false, serverid_ok = false, rcauth_ok = false,
 546                 ia_present = false, options_valid = true;
 547
 548         size_t client_id_len, server_id_len;
 549         void *client_id = odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
 550         void *server_id = odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
 551
 552         dhcpv6_for_each_option(&rep[1], end, otype, olen, odata) {
 553                 if (otype == DHCPV6_OPT_CLIENTID) {
 554                         clientid_ok = (olen + 4U == client_id_len) && !memcmp(
 555                                         &odata[-4], client_id, client_id_len);
 556                 } else if (otype == DHCPV6_OPT_SERVERID) {
 557                         if (server_id_len)
 558                                 serverid_ok = (olen + 4U == server_id_len) && !memcmp(
 559                                                 &odata[-4], server_id, server_id_len);
 560                         else
 561                                 serverid_ok = true;
 562                 } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
 563                                 sizeof(struct dhcpv6_auth_reconfigure)) {
 564                         struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
 565                         if (r->protocol != 3 || r->algorithm != 1 || r->reconf_type != 2)
 566                                 continue;
 567
 568                         md5_state_t md5;
 569                         uint8_t serverhash[16], secretbytes[16], hash[16];
 570                         memcpy(serverhash, r->key, sizeof(serverhash));
 571                         memset(r->key, 0, sizeof(r->key));
 572                         memcpy(secretbytes, reconf_key, sizeof(secretbytes));
 573
 574                         for (size_t i = 0; i < sizeof(secretbytes); ++i)
 575                                 secretbytes[i] ^= 0x36;
 576
 577                         md5_init(&md5);
 578                         md5_append(&md5, secretbytes, sizeof(secretbytes));
 579                         md5_append(&md5, buf, len);
 580                         md5_finish(&md5, hash);
 581
 582                         for (size_t i = 0; i < sizeof(secretbytes); ++i) {
 583                                 secretbytes[i] ^= 0x36;
 584                                 secretbytes[i] ^= 0x5c;
 585                         }
 586
 587                         md5_init(&md5);
 588                         md5_append(&md5, secretbytes, sizeof(secretbytes));
 589                         md5_append(&md5, hash, 16);
 590                         md5_finish(&md5, hash);
 591
 592                         rcauth_ok = !memcmp(hash, serverhash, sizeof(hash));
 593                 } else if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1) {
 594                         rcmsg = odata[0];
 595                 } else if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)) {
 596                         ia_present = true;
 597                         if (olen < sizeof(struct dhcpv6_ia_hdr))
 598                                 options_valid = false;
 599                 }
 600                 else if ((otype == DHCPV6_OPT_IA_ADDR) || (otype == DHCPV6_OPT_IA_PREFIX) ||
 601                                 (otype == DHCPV6_OPT_PD_EXCLUDE)) {
 602                         // Options are not allowed on global level
 603                         options_valid = false;
 604                 }
 605         }
 606
 607         if (!options_valid)
 608                 return false;
 609
 610         if (type == DHCPV6_MSG_INFO_REQ && ia_present)
 611                 return false;
 612
 613         if (rep->msg_type == DHCPV6_MSG_RECONF) {
 614                 if ((rcmsg != DHCPV6_MSG_RENEW && rcmsg != DHCPV6_MSG_INFO_REQ) ||
 615                         (rcmsg == DHCPV6_MSG_INFO_REQ && ia_present) ||
 616                         !rcauth_ok || IN6_IS_ADDR_MULTICAST(daddr))
 617                         return false;
 618         }
 619
 620         return clientid_ok && serverid_ok;
 621 }
 622
 623
 624 int dhcpv6_poll_reconfigure(void)
 625 {
 626         int ret = dhcpv6_request(DHCPV6_MSG_UNKNOWN);
 627         if (ret != -1)
 628                 ret = dhcpv6_request(ret);
 629
 630         return ret;
 631 }
 632
 633
 634 static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig, const int rc,
 635                 const void *opt, const void *end)
 636 {
 637         uint16_t otype, olen;
 638         uint8_t *odata, msg = DHCPV6_MSG_RENEW;
 639         dhcpv6_for_each_option(opt, end, otype, olen, odata)
 640                 if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1 && (
 641                                 odata[0] == DHCPV6_MSG_RENEW ||
 642                                 odata[0] == DHCPV6_MSG_INFO_REQ))
 643                         msg = odata[0];
 644
 645         dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, rc, NULL, NULL);
 646         return msg;
 647 }
 648
 649
 650 // Collect all advertised servers
 651 static int dhcpv6_handle_advert(enum dhcpv6_msg orig, const int rc,
 652                 const void *opt, const void *end)
 653 {
 654         uint16_t olen, otype;
 655         uint8_t *odata, pref = 0;
 656         struct dhcpv6_server_cand cand = {false, false, 0, 0, {0}, NULL, NULL, 0, 0};
 657         bool have_na = false;
 658         int have_pd = 0;
 659
 660         dhcpv6_for_each_option(opt, end, otype, olen, odata) {
 661                 if (orig == DHCPV6_MSG_SOLICIT &&
 662                                 (otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA) &&
 663                                 olen > sizeof(struct dhcpv6_ia_hdr)) {
 664                         struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
 665                         dhcpv6_parse_ia(ia_hdr, odata + olen + sizeof(*ia_hdr));
 666                 }
 667
 668                 if (otype == DHCPV6_OPT_SERVERID && olen <= 130) {
 669                         memcpy(cand.duid, odata, olen);
 670                         cand.duid_len = olen;
 671                 } else if (otype == DHCPV6_OPT_STATUS && olen >= 2) {
 672                         int error = ((int)odata[0] << 8 | (int)odata[1]);
 673
 674                         switch (error) {
 675                         case DHCPV6_NoPrefixAvail:
 676                                 // Status code on global level
 677                                 if (pd_mode == IA_MODE_FORCE)
 678                                         return -1;
 679                                 cand.preference -= 2000;
 680                                 break;
 681
 682                         case DHCPV6_NoAddrsAvail:
 683                                 // Status code on global level
 684                                 if (na_mode == IA_MODE_FORCE)
 685                                         return -1;
 686                                 break;
 687
 688                         default :
 689                                 break;
 690                         }
 691                 } else if (otype == DHCPV6_OPT_PREF && olen >= 1 &&
 692                                 cand.preference >= 0) {
 693                         cand.preference = pref = odata[0];
 694                 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
 695                         cand.wants_reconfigure = true;
 696                 } else if (otype == DHCPV6_OPT_IA_PD && request_prefix) {
 697                         struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
 698                         uint8_t *oend = odata + olen, *d;
 699                         dhcpv6_for_each_option(&h[1], oend, otype, olen, d) {
 700                                 if (otype == DHCPV6_OPT_IA_PREFIX && (olen + 4) >=
 701                                                 (uint16_t)sizeof(struct dhcpv6_ia_prefix)) {
 702                                         struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&d[-4];
 703                                         have_pd = p->prefix;
 704                                 }
 705                         }
 706                 } else if (otype == DHCPV6_OPT_IA_NA) {
 707                         struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
 708                         uint8_t *oend = odata + olen, *d;
 709                         dhcpv6_for_each_option(&h[1], oend, otype, olen, d)
 710                                 if (otype == DHCPV6_OPT_IA_ADDR)
 711                                         have_na = true;
 712                 }
 713         }
 714
 715         if ((!have_na && na_mode == IA_MODE_FORCE) ||
 716                         (!have_pd && pd_mode == IA_MODE_FORCE))
 717                 return -1;
 718
 719         if (na_mode != IA_MODE_NONE && !have_na) {
 720                 cand.has_noaddravail = true;
 721                 cand.preference -= 1000;
 722         }
 723
 724         if (pd_mode != IA_MODE_NONE) {
 725                 if (have_pd)
 726                         cand.preference += 2000 + (128 - have_pd);
 727                 else
 728                         cand.preference -= 2000;
 729         }
 730
 731         if (cand.duid_len > 0) {
 732                 cand.ia_na = odhcp6c_move_state(STATE_IA_NA, &cand.ia_na_len);
 733                 cand.ia_pd = odhcp6c_move_state(STATE_IA_PD, &cand.ia_pd_len);
 734                 odhcp6c_add_state(STATE_SERVER_CAND, &cand, sizeof(cand));
 735         }
 736
 737         return (rc > 1 || (pref == 255 && cand.preference > 0)) ? 1 : -1;
 738 }
 739
 740
 741 static int dhcpv6_commit_advert(void)
 742 {
 743         size_t cand_len;
 744         struct dhcpv6_server_cand *c = NULL, *cand =
 745                         odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
 746
 747         bool retry = false;
 748         for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
 749                 if (cand[i].has_noaddravail)
 750                         retry = true; // We want to try again
 751
 752                 if (!c || c->preference < cand[i].preference)
 753                         c = &cand[i];
 754         }
 755
 756         if (retry && na_mode == IA_MODE_TRY) {
 757                 // We give it a second try without the IA_NA
 758                 na_mode = IA_MODE_NONE;
 759                 return dhcpv6_request(DHCPV6_MSG_SOLICIT);
 760         }
 761
 762         if (c) {
 763                 uint16_t hdr[2] = {htons(DHCPV6_OPT_SERVERID),
 764                                 htons(c->duid_len)};
 765                 odhcp6c_add_state(STATE_SERVER_ID, hdr, sizeof(hdr));
 766                 odhcp6c_add_state(STATE_SERVER_ID, c->duid, c->duid_len);
 767                 accept_reconfig = c->wants_reconfigure;
 768                 if (c->ia_na_len)
 769                         odhcp6c_add_state(STATE_IA_NA, c->ia_na, c->ia_na_len);
 770                 if (c->ia_pd_len)
 771                         odhcp6c_add_state(STATE_IA_PD, c->ia_pd, c->ia_pd_len);
 772         }
 773
 774         for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
 775                 free(cand[i].ia_na);
 776                 free(cand[i].ia_pd);
 777         }
 778         odhcp6c_clear_state(STATE_SERVER_CAND);
 779
 780         if (!c)
 781                 return -1;
 782         else if ((request_prefix && c->ia_pd_len) || (na_mode != IA_MODE_NONE && c->ia_na_len))
 783                 return DHCPV6_STATEFUL;
 784         else
 785                 return DHCPV6_STATELESS;
 786 }
 787
 788
 789 static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig, const int rc,
 790                 const void *opt, const void *end)
 791 {
 792         dhcpv6_handle_advert(orig, rc, opt, end);
 793         if (dhcpv6_commit_advert() < 0)
 794                 return -1;
 795
 796         return dhcpv6_handle_reply(orig, rc, opt, end);
 797 }
 798
 799
 800 static int dhcpv6_handle_reply(enum dhcpv6_msg orig, _unused const int rc,
 801                 const void *opt, const void *end)
 802 {
 803         uint8_t *odata;
 804         uint16_t otype, olen;
 805         uint32_t refresh = UINT32_MAX;
 806         int ret = 1;
 807         bool handled_status_codes[_DHCPV6_Status_Max] = { false, };
 808
 809         odhcp6c_expire();
 810
 811         if (orig == DHCPV6_MSG_UNKNOWN) {
 812                 static time_t last_update = 0;
 813                 time_t now = odhcp6c_get_milli_time() / 1000;
 814
 815                 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
 816                 last_update = now;
 817
 818                 t1 -= elapsed;
 819                 t2 -= elapsed;
 820                 t3 -= elapsed;
 821
 822                 if (t1 < 0)
 823                         t1 = 0;
 824
 825                 if (t2 < 0)
 826                         t2 = 0;
 827
 828                 if (t3 < 0)
 829                         t3 = 0;
 830         }
 831
 832         if (orig == DHCPV6_MSG_REQUEST && !odhcp6c_is_bound()) {
 833                 // Delete NA and PD we have in the state from the Advert
 834                 odhcp6c_clear_state(STATE_IA_NA);
 835                 odhcp6c_clear_state(STATE_IA_PD);
 836         }
 837
 838         if (opt) {
 839                 odhcp6c_clear_state(STATE_DNS);
 840                 odhcp6c_clear_state(STATE_SEARCH);
 841                 odhcp6c_clear_state(STATE_SNTP_IP);
 842                 odhcp6c_clear_state(STATE_SNTP_FQDN);
 843                 odhcp6c_clear_state(STATE_SIP_IP);
 844                 odhcp6c_clear_state(STATE_SIP_FQDN);
 845                 odhcp6c_clear_state(STATE_AFTR_NAME);
 846         }
 847
 848         // Parse and find all matching IAs
 849         dhcpv6_for_each_option(opt, end, otype, olen, odata) {
 850                 if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)
 851                                 && olen > sizeof(struct dhcpv6_ia_hdr)) {
 852                         struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
 853
 854                         // Test ID
 855                         if (ia_hdr->iaid != 1)
 856                                 continue;
 857
 858                         uint16_t code = DHCPV6_Success;
 859                         uint16_t stype, slen;
 860                         uint8_t *sdata;
 861                         // Get and handle status code
 862                         dhcpv6_for_each_option(&ia_hdr[1], odata + olen,
 863                                         stype, slen, sdata) {
 864                                 if (stype == DHCPV6_OPT_STATUS && slen >= 2) {
 865                                         uint8_t *mdata = (slen > 2) ? &sdata[2] : NULL;
 866                                         uint16_t mlen = (slen > 2) ? slen - 2 : 0;
 867
 868                                         code = ((int)sdata[0]) << 8 | ((int)sdata[1]);
 869
 870                                         if (code == DHCPV6_Success)
 871                                                 continue;
 872
 873                                         dhcpv6_handle_ia_status_code(orig, ia_hdr,
 874                                                 code, mdata, mlen, handled_status_codes, &ret);
 875
 876
 877                                         if (ret > 0)
 878                                                 return ret;
 879                                         break;
 880                                 }
 881                         }
 882
 883                         if (code != DHCPV6_Success)
 884                                 continue;
 885
 886                         dhcpv6_parse_ia(ia_hdr, odata + olen + sizeof(*ia_hdr));
 887                 } else if (otype == DHCPV6_OPT_STATUS && olen >= 2) {
 888                         uint8_t *mdata = (olen > 2) ? &odata[2] : NULL;
 889                         uint16_t mlen = (olen > 2) ? olen - 2 : 0;
 890                         uint16_t code = ((int)odata[0]) << 8 | ((int)odata[1]);
 891
 892                         dhcpv6_handle_status_code(orig, code, mdata, mlen, &ret);
 893                 }
 894                 else if (otype == DHCPV6_OPT_DNS_SERVERS) {
 895                         if (olen % 16 == 0)
 896                                 odhcp6c_add_state(STATE_DNS, odata, olen);
 897                 } else if (otype == DHCPV6_OPT_DNS_DOMAIN) {
 898                         odhcp6c_add_state(STATE_SEARCH, odata, olen);
 899                 } else if (otype == DHCPV6_OPT_NTP_SERVER) {
 900                         uint16_t stype, slen;
 901                         uint8_t *sdata;
 902                         // Test status and bail if error
 903                         dhcpv6_for_each_option(odata, odata + olen,
 904                                         stype, slen, sdata) {
 905                                 if (slen == 16 && (stype == NTP_MC_ADDR ||
 906                                                 stype == NTP_SRV_ADDR))
 907                                         odhcp6c_add_state(STATE_SNTP_IP,
 908                                                         sdata, slen);
 909                                 else if (slen > 0 && stype == NTP_SRV_FQDN)
 910                                         odhcp6c_add_state(STATE_SNTP_FQDN,
 911                                                         sdata, slen);
 912                         }
 913                 } else if (otype == DHCPV6_OPT_SIP_SERVER_A) {
 914                         if (olen == 16)
 915                                 odhcp6c_add_state(STATE_SIP_IP, odata, olen);
 916                 } else if (otype == DHCPV6_OPT_SIP_SERVER_D) {
 917                         odhcp6c_add_state(STATE_SIP_FQDN, odata, olen);
 918                 } else if (otype == DHCPV6_OPT_INFO_REFRESH && olen >= 4) {
 919                         refresh = ntohl(*((uint32_t*)odata));
 920                 } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
 921                                 sizeof(struct dhcpv6_auth_reconfigure)) {
 922                         struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
 923                         if (r->protocol == 3 && r->algorithm == 1 &&
 924                                         r->reconf_type == 1)
 925                                 memcpy(reconf_key, r->key, sizeof(r->key));
 926                 } else if (otype == DHCPV6_OPT_AFTR_NAME && olen > 3) {
 927                         size_t cur_len;
 928                         odhcp6c_get_state(STATE_AFTR_NAME, &cur_len);
 929                         if (cur_len == 0)
 930                                 odhcp6c_add_state(STATE_AFTR_NAME, odata, olen);
 931                 } else if (otype != DHCPV6_OPT_CLIENTID &&
 932                                 otype != DHCPV6_OPT_SERVERID) {
 933                         odhcp6c_add_state(STATE_CUSTOM_OPTS,
 934                                         &odata[-4], olen + 4);
 935                 }
 936         }
 937
 938         if (orig != DHCPV6_MSG_INFO_REQ) {
 939                 // Update refresh timers if no fatal status code was received
 940                 if ((ret > 0) && dhcpv6_calc_refresh_timers()) {
 941                         switch (orig) {
 942                         case DHCPV6_MSG_RENEW:
 943                                 // Send further renews if T1 is not set
 944                                 if (!t1)
 945                                         ret = -1;
 946                                 break;
 947                         case DHCPV6_MSG_REBIND:
 948                                 // Send further rebinds if T1 and T2 is not set
 949                                 if (!t1 && !t2)
 950                                         ret = -1;
 951                                 break;
 952
 953                         default :
 954                                 break;
 955                         }
 956                 }
 957         }
 958         else if (ret > 0)
 959                 t1 = refresh;
 960
 961         return ret;
 962 }
 963
 964
 965 static int dhcpv6_parse_ia(void *opt, void *end)
 966 {
 967         struct dhcpv6_ia_hdr *ia_hdr = (struct dhcpv6_ia_hdr *)opt;
 968         int parsed_ia = 0;
 969         uint32_t t1, t2;
 970         uint16_t otype, olen;
 971         uint8_t *odata;
 972
 973         t1 = ntohl(ia_hdr->t1);
 974         t2 = ntohl(ia_hdr->t2);
 975
 976         if (t1 > t2)
 977                 return 0;
 978
 979         // Update address IA
 980         dhcpv6_for_each_option(&ia_hdr[1], end, otype, olen, odata) {
 981                 struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0,
 982                                 IN6ADDR_ANY_INIT, 0, 0, 0, 0, 0};
 983
 984                 if (otype == DHCPV6_OPT_IA_PREFIX) {
 985                         struct dhcpv6_ia_prefix *prefix = (void*)&odata[-4];
 986                         if (olen + 4U < sizeof(*prefix))
 987                                 continue;
 988
 989                         entry.valid = ntohl(prefix->valid);
 990                         entry.preferred = ntohl(prefix->preferred);
 991
 992                         if (entry.preferred > entry.valid)
 993                                 continue;
 994
 995                         entry.t1 = (t1 ? t1 : (entry.preferred != UINT32_MAX ? 0.5 * entry.preferred : UINT32_MAX));
 996                         entry.t2 = (t2 ? t2 : (entry.preferred != UINT32_MAX ? 0.8 * entry.preferred : UINT32_MAX));
 997                         if (entry.t1 > entry.t2)
 998                                 entry.t1 = entry.t2;
 999
1000                         entry.length = prefix->prefix;
1001                         entry.target = prefix->addr;
1002                         uint16_t stype, slen;
1003                         uint8_t *sdata;
1004
1005 #ifdef EXT_PREFIX_CLASS
1006                         // Find prefix class, if any
1007                         dhcpv6_for_each_option(&prefix[1], odata + olen,
1008                                         stype, slen, sdata)
1009                                 if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
1010                                         entry.class = sdata[0] << 8 | sdata[1];
1011 #endif
1012
1013                         // Parse PD-exclude
1014                         bool ok = true;
1015                         dhcpv6_for_each_option(odata + sizeof(*prefix) - 4U,
1016                                         odata + olen, stype, slen, sdata) {
1017                                 if (stype != DHCPV6_OPT_PD_EXCLUDE || slen < 2)
1018                                         continue;
1019
1020                                 uint8_t elen = sdata[0];
1021                                 if (elen > 64)
1022                                         elen = 64;
1023
1024                                 if (elen <= 32 || elen <= entry.length) {
1025                                         ok = false;
1026                                         continue;
1027                                 }
1028
1029
1030                                 uint8_t bytes = ((elen - entry.length - 1) / 8) + 1;
1031                                 if (slen <= bytes) {
1032                                         ok = false;
1033                                         continue;
1034                                 }
1035
1036                                 uint32_t exclude = 0;
1037                                 do {
1038                                         exclude = exclude << 8 | sdata[bytes];
1039                                 } while (--bytes);
1040
1041                                 exclude >>= 8 - ((elen - entry.length) % 8);
1042                                 exclude <<= 64 - elen;
1043
1044                                 // Abusing router & priority fields for exclusion
1045                                 entry.router = entry.target;
1046                                 entry.router.s6_addr32[1] |= htonl(exclude);
1047                                 entry.priority = elen;
1048                         }
1049
1050                         if (ok) {
1051                                 odhcp6c_update_entry(STATE_IA_PD, &entry);
1052                                 parsed_ia++;
1053                         }
1054
1055                         entry.priority = 0;
1056                         memset(&entry.router, 0, sizeof(entry.router));
1057                 } else if (otype == DHCPV6_OPT_IA_ADDR) {
1058                         struct dhcpv6_ia_addr *addr = (void*)&odata[-4];
1059                         if (olen + 4U < sizeof(*addr))
1060                                 continue;
1061
1062                         entry.preferred = ntohl(addr->preferred);
1063                         entry.valid = ntohl(addr->valid);
1064
1065                         if (entry.preferred > entry.valid)
1066                                 continue;
1067
1068                         entry.t1 = (t1 ? t1 : (entry.preferred != UINT32_MAX ? 0.5 * entry.preferred : UINT32_MAX));
1069                         entry.t2 = (t2 ? t2 : (entry.preferred != UINT32_MAX ? 0.8 * entry.preferred : UINT32_MAX));
1070                         if (entry.t1 > entry.t2)
1071                                 entry.t1 = entry.t2;
1072
1073                         entry.length = 128;
1074                         entry.target = addr->addr;
1075
1076 #ifdef EXT_PREFIX_CLASS
1077                         uint16_t stype, slen;
1078                         uint8_t *sdata;
1079                         // Find prefix class, if any
1080                         dhcpv6_for_each_option(&addr[1], odata + olen,
1081                                         stype, slen, sdata)
1082                                 if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
1083                                         entry.class = sdata[0] << 8 | sdata[1];
1084 #endif
1085
1086                         odhcp6c_update_entry(STATE_IA_NA, &entry);
1087                         parsed_ia++;
1088                 }
1089         }
1090         return parsed_ia;
1091 }
1092
1093
1094 static int dhcpv6_calc_refresh_timers(void)
1095 {
1096         struct odhcp6c_entry *e;
1097         size_t ia_na_entries, ia_pd_entries, i;
1098         int64_t l_t1 = UINT32_MAX, l_t2 = UINT32_MAX, l_t3 = 0;
1099
1100         e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
1101         ia_na_entries /= sizeof(*e);
1102         for (i = 0; i < ia_na_entries; i++) {
1103                 if (e[i].t1 < l_t1)
1104                         l_t1 = e[i].t1;
1105
1106                 if (e[i].t2 < l_t2)
1107                         l_t2 = e[i].t2;
1108
1109                 if (e[i].valid > l_t3)
1110                         l_t3 = e[i].valid;
1111         }
1112
1113         e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
1114         ia_pd_entries /= sizeof(*e);
1115         for (i = 0; i < ia_pd_entries; i++) {
1116                 if (e[i].t1 < l_t1)
1117                         l_t1 = e[i].t1;
1118
1119                 if (e[i].t2 < l_t2)
1120                         l_t2 = e[i].t2;
1121
1122                 if (e[i].valid > l_t3)
1123                         l_t3 = e[i].valid;
1124         }
1125
1126         if (ia_pd_entries || ia_na_entries) {
1127                 t1 = l_t1;
1128                 t2 = l_t2;
1129                 t3 = l_t3;
1130         }
1131
1132         return (int)(ia_pd_entries + ia_na_entries);
1133 }
1134
1135
1136 static void dhcpv6_log_status_code(const uint16_t code, const char *scope,
1137                 const void *status_msg, const int len)
1138 {
1139         uint8_t buf[len + 3];
1140
1141         memset(buf, 0, sizeof(buf));
1142         if (len) {
1143                 buf[0] = '(';
1144                 memcpy(&buf[1], status_msg, len);
1145                 buf[len + 1] = ')';
1146         }
1147
1148         syslog(LOG_WARNING, "Server returned %s status %i %s",
1149                 scope, code, buf);
1150 }
1151
1152
1153 static void dhcpv6_handle_status_code(const enum dhcpv6_msg orig,
1154                 const uint16_t code, const void *status_msg, const int len,
1155                 int *ret)
1156 {
1157         dhcpv6_log_status_code(code, "message", status_msg, len);
1158
1159         switch (code) {
1160         case DHCPV6_UnspecFail:
1161                 // Generic failure
1162                 *ret = 0;
1163                 break;
1164
1165         case DHCPV6_UseMulticast:
1166                 // TODO handle multicast status code
1167                 break;
1168
1169         case DHCPV6_NoAddrsAvail:
1170         case DHCPV6_NoPrefixAvail:
1171                 if (orig == DHCPV6_MSG_REQUEST)
1172                         *ret = 0; // Failure
1173                 break;
1174
1175         default:
1176                 break;
1177         }
1178 }
1179
1180
1181 static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig,
1182                 const struct dhcpv6_ia_hdr *ia_hdr, const uint16_t code,
1183                 const void *status_msg, const int len,
1184                 bool handled_status_codes[_DHCPV6_Status_Max], int *ret)
1185 {
1186         dhcpv6_log_status_code(code, ia_hdr->type == DHCPV6_OPT_IA_NA ?
1187                 "IA_NA" : "IA_PD", status_msg, len);
1188
1189         switch (code) {
1190         case DHCPV6_NoBinding:
1191                 switch (orig) {
1192                 case DHCPV6_MSG_RENEW:
1193                 case DHCPV6_MSG_REBIND:
1194                         if ((*ret > 0) && !handled_status_codes[code])
1195                                 *ret = dhcpv6_request(DHCPV6_MSG_REQUEST);
1196                         break;
1197
1198                 default:
1199                         break;
1200                 }
1201                 break;
1202
1203         case DHCPV6_NoAddrsAvail:
1204         case DHCPV6_NoPrefixAvail:
1205                 switch (orig) {
1206                 case DHCPV6_MSG_REQUEST:
1207                         if (*ret != 0)
1208                                 *ret = 0;
1209                         break;
1210                 default:
1211                         break;
1212                 }
1213                 break;
1214
1215         case DHCPV6_NotOnLink:
1216                 // TODO handle not onlink in case of confirm
1217                 break;
1218
1219         default:
1220                 break;
1221         }
1222 }