2 * Copyright (C) 2012-2013 Steven Barth <steven@midlink.org>
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.
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.
27 #include <sys/ioctl.h>
28 #include <sys/socket.h>
29 #include <netinet/in.h>
32 #include <net/ethernet.h>
37 #define ALL_DHCPV6_RELAYS {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
38 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x02}}}
39 #define DHCPV6_CLIENT_PORT 546
40 #define DHCPV6_SERVER_PORT 547
41 #define DHCPV6_DUID_LLADDR 3
42 #define DHCPV6_REQ_DELAY 1
45 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
46 const uint8_t transaction[3], enum dhcpv6_msg type);
48 static uint32_t dhcpv6_parse_ia(void *opt, void *end);
50 static reply_handler dhcpv6_handle_reply;
51 static reply_handler dhcpv6_handle_advert;
52 static reply_handler dhcpv6_handle_rebind_reply;
53 static reply_handler dhcpv6_handle_reconfigure;
54 static int dhcpv6_commit_advert(void);
58 // RFC 3315 - 5.5 Timeout and Delay values
59 static struct dhcpv6_retx dhcpv6_retx[_DHCPV6_MSG_MAX] = {
60 [DHCPV6_MSG_UNKNOWN] = {false, 1, 120, "<POLL>",
61 dhcpv6_handle_reconfigure, NULL},
62 [DHCPV6_MSG_SOLICIT] = {true, 1, 120, "SOLICIT",
63 dhcpv6_handle_advert, dhcpv6_commit_advert},
64 [DHCPV6_MSG_REQUEST] = {true, 30, 10, "REQUEST",
65 dhcpv6_handle_reply, NULL},
66 [DHCPV6_MSG_RENEW] = {false, 10, 600, "RENEW",
67 dhcpv6_handle_reply, NULL},
68 [DHCPV6_MSG_REBIND] = {false, 10, 600, "REBIND",
69 dhcpv6_handle_rebind_reply, NULL},
70 [DHCPV6_MSG_RELEASE] = {false, 1, 600, "RELEASE", NULL, NULL},
71 [DHCPV6_MSG_DECLINE] = {false, 1, 3, "DECLINE", NULL, NULL},
72 [DHCPV6_MSG_INFO_REQ] = {true, 1, 120, "INFOREQ",
73 dhcpv6_handle_reply, NULL},
79 static int ifindex = -1;
80 static int64_t t1 = 0, t2 = 0, t3 = 0;
83 static int request_prefix = -1;
84 static enum odhcp6c_ia_mode na_mode = IA_MODE_NONE;
85 static bool accept_reconfig = false;
89 int init_dhcpv6(const char *ifname, int request_pd)
91 request_prefix = request_pd;
93 sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
97 strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
98 if (ioctl(sock, SIOCGIFINDEX, &ifr))
100 ifindex = ifr.ifr_ifindex;
102 // Create client DUID
103 size_t client_id_len;
104 odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
105 if (client_id_len == 0) {
106 ioctl(sock, SIOCGIFHWADDR, &ifr);
107 uint8_t duid[14] = {0, DHCPV6_OPT_CLIENTID, 0, 10, 0,
108 DHCPV6_DUID_LLADDR, 0, 1};
109 memcpy(&duid[8], ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
111 uint8_t zero[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
112 struct ifreq ifs[100], *ifp, *ifend;
115 ifc.ifc_len = sizeof(ifs);
117 if (!memcmp(&duid[8], zero, ETHER_ADDR_LEN) &&
118 ioctl(sock, SIOCGIFCONF, &ifc) >= 0) {
119 // If our interface doesn't have an address...
120 ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq));
121 for (ifp = ifc.ifc_req; ifp < ifend &&
122 !memcmp(&duid[8], zero, 6); ifp++) {
123 memcpy(ifr.ifr_name, ifp->ifr_name,
124 sizeof(ifr.ifr_name));
125 ioctl(sock, SIOCGIFHWADDR, &ifr);
126 memcpy(&duid[8], ifr.ifr_hwaddr.sa_data,
131 odhcp6c_add_state(STATE_CLIENT_ID, duid, sizeof(duid));
135 uint16_t oro[] = {htons(DHCPV6_OPT_DNS_SERVERS),
136 htons(DHCPV6_OPT_DNS_DOMAIN),
137 htons(DHCPV6_OPT_NTP_SERVER),
138 htons(DHCPV6_OPT_SIP_SERVER_A),
139 htons(DHCPV6_OPT_SIP_SERVER_D),
140 htons(DHCPV6_OPT_PD_EXCLUDE)};
141 odhcp6c_add_state(STATE_ORO, oro, sizeof(oro));
144 // Configure IPv6-options
146 setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val));
147 setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
148 setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
150 struct sockaddr_in6 client_addr = { .sin6_family = AF_INET6,
151 .sin6_port = htons(DHCPV6_CLIENT_PORT), .sin6_flowinfo = 0 };
152 if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr)))
159 void dhcpv6_set_ia_na_mode(enum odhcp6c_ia_mode mode)
165 static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
169 gethostname(fqdn_buf, sizeof(fqdn_buf));
176 size_t fqdn_len = 5 + dn_comp(fqdn_buf, fqdn.data,
177 sizeof(fqdn.data), NULL, NULL);
178 fqdn.type = htons(DHCPV6_OPT_FQDN);
179 fqdn.len = htons(fqdn_len - 4);
185 void *cl_id = odhcp6c_get_state(STATE_CLIENT_ID, &cl_id_len);
189 void *srv_id = odhcp6c_get_state(STATE_SERVER_ID, &srv_id_len);
192 size_t ia_pd_entries, ia_pd_len = 0;
193 struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
194 ia_pd_entries /= sizeof(*e);
195 struct dhcpv6_ia_hdr hdr_ia_pd = {
196 htons(DHCPV6_OPT_IA_PD),
197 htons(sizeof(hdr_ia_pd) - 4),
202 uint8_t *ia_pd = alloca(ia_pd_entries * (sizeof(struct dhcpv6_ia_prefix) + 10));
203 for (size_t i = 0; i < ia_pd_entries; ++i) {
205 if (e[i].priority > 0)
206 ex_len = ((e[i].priority - e[i].length - 1) / 8) + 6;
208 struct dhcpv6_ia_prefix p = {
209 .type = htons(DHCPV6_OPT_IA_PREFIX),
210 .len = htons(sizeof(p) - 4U + ex_len),
211 .prefix = e[i].length,
215 memcpy(ia_pd + ia_pd_len, &p, sizeof(p));
216 ia_pd_len += sizeof(p);
219 ia_pd[ia_pd_len++] = 0;
220 ia_pd[ia_pd_len++] = DHCPV6_OPT_PD_EXCLUDE;
221 ia_pd[ia_pd_len++] = 0;
222 ia_pd[ia_pd_len++] = ex_len - 4;
223 ia_pd[ia_pd_len++] = e[i].priority;
225 uint32_t excl = ntohl(e[i].router.s6_addr32[1]);
226 excl >>= (64 - e[i].priority);
227 excl <<= 8 - ((e[i].priority - e[i].length) % 8);
229 for (size_t i = ex_len - 5; i > 0; --i, excl >>= 8)
230 ia_pd[ia_pd_len + i] = excl & 0xff;
231 ia_pd_len += ex_len - 5;
235 struct dhcpv6_ia_prefix pref = {
236 .type = htons(DHCPV6_OPT_IA_PREFIX),
237 .len = htons(25), .prefix = request_prefix
239 if (request_prefix > 0 && ia_pd_len == 0 &&
240 (type == DHCPV6_MSG_SOLICIT ||
241 type == DHCPV6_MSG_REQUEST)) {
242 ia_pd = (uint8_t*)&pref;
243 ia_pd_len = sizeof(pref);
245 hdr_ia_pd.len = htons(ntohs(hdr_ia_pd.len) + ia_pd_len);
248 size_t ia_na_entries, ia_na_len = 0;
250 e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
251 ia_na_entries /= sizeof(*e);
253 struct dhcpv6_ia_hdr hdr_ia_na = {
254 htons(DHCPV6_OPT_IA_NA),
255 htons(sizeof(hdr_ia_na) - 4),
259 struct dhcpv6_ia_addr pa[ia_na_entries];
260 for (size_t i = 0; i < ia_na_entries; ++i) {
261 pa[i].type = htons(DHCPV6_OPT_IA_ADDR);
262 pa[i].len = htons(sizeof(pa[i]) - 4U);
263 pa[i].addr = e[i].target;
269 ia_na_len = sizeof(pa);
270 hdr_ia_na.len = htons(ntohs(hdr_ia_na.len) + ia_na_len);
272 // Reconfigure Accept
276 } reconf_accept = {htons(DHCPV6_OPT_RECONF_ACCEPT), 0};
278 // Request Information Refresh
279 uint16_t oro_refresh = htons(DHCPV6_OPT_INFO_REFRESH);
283 void *oro = odhcp6c_get_state(STATE_ORO, &oro_len);
287 uint16_t elapsed_type;
288 uint16_t elapsed_len;
289 uint16_t elapsed_value;
293 type, {trid[0], trid[1], trid[2]},
294 htons(DHCPV6_OPT_ELAPSED), htons(2),
295 htons((ecs > 0xffff) ? 0xffff : ecs),
296 htons(DHCPV6_OPT_ORO), htons(oro_len),
299 struct iovec iov[] = {
304 {srv_id, srv_id_len},
307 {&hdr_ia_na, sizeof(hdr_ia_na)},
309 {&hdr_ia_pd, sizeof(hdr_ia_pd)},
313 size_t cnt = ARRAY_SIZE(iov);
314 if (type == DHCPV6_MSG_INFO_REQ) {
316 iov[2].iov_len = sizeof(oro_refresh);
317 hdr.oro_len = htons(oro_len + sizeof(oro_refresh));
318 } else if (!request_prefix) {
322 // Disable IAs if not used
323 if (type == DHCPV6_MSG_SOLICIT) {
324 iov[5].iov_len = sizeof(reconf_accept);
325 } else if (type != DHCPV6_MSG_REQUEST) {
332 if (na_mode == IA_MODE_NONE)
335 struct sockaddr_in6 srv = {AF_INET6, htons(DHCPV6_SERVER_PORT),
336 0, ALL_DHCPV6_RELAYS, ifindex};
337 struct msghdr msg = {&srv, sizeof(srv), iov, cnt, NULL, 0, 0};
339 sendmsg(sock, &msg, 0);
343 static int64_t dhcpv6_rand_delay(int64_t time)
346 odhcp6c_random(&random, sizeof(random));
347 return (time * (random % 1000)) / 10000;
351 int dhcpv6_request(enum dhcpv6_msg type)
354 uint32_t timeout = UINT32_MAX;
355 struct dhcpv6_retx *retx = &dhcpv6_retx[type];
358 struct timespec ts = {0, 0};
359 ts.tv_nsec = dhcpv6_rand_delay(10 * DHCPV6_REQ_DELAY);
360 nanosleep(&ts, NULL);
363 if (type == DHCPV6_MSG_RELEASE || type == DHCPV6_MSG_DECLINE)
365 else if (type == DHCPV6_MSG_UNKNOWN)
367 else if (type == DHCPV6_MSG_RENEW)
369 else if (type == DHCPV6_MSG_REBIND)
375 syslog(LOG_NOTICE, "Sending %s (timeout %us)", retx->name, timeout);
377 uint64_t start = odhcp6c_get_milli_time(), round_start = start, elapsed;
379 // Generate transaction ID
381 odhcp6c_random(trid, sizeof(trid));
386 rto = (rto == 0) ? (retx->init_timeo * 1000 +
387 dhcpv6_rand_delay(retx->init_timeo * 1000)) :
388 (2 * rto + dhcpv6_rand_delay(rto));
390 if (rto >= retx->max_timeo * 1000)
391 rto = retx->max_timeo * 1000 +
392 dhcpv6_rand_delay(retx->max_timeo * 1000);
394 // Calculate end for this round and elapsed time
395 uint64_t round_end = round_start + rto;
396 elapsed = round_start - start;
398 // Don't wait too long
399 if (round_end - start > timeout * 1000)
400 round_end = timeout * 1000 + start;
402 // Built and send package
403 if (type != DHCPV6_MSG_UNKNOWN)
404 dhcpv6_send(type, trid, elapsed / 10);
407 for (; len < 0 && round_start < round_end;
408 round_start = odhcp6c_get_milli_time()) {
409 // Check for pending signal
410 if (odhcp6c_signal_process())
413 // Set timeout for receiving
414 uint64_t t = round_end - round_start;
415 struct timeval timeout = {t / 1000, (t % 1000) * 1000};
416 setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO,
417 &timeout, sizeof(timeout));
420 len = recv(sock, buf, sizeof(buf), 0);
422 if (!dhcpv6_response_is_valid(buf, len, trid, type))
426 uint8_t *opt = &buf[4];
427 uint8_t *opt_end = opt + len - 4;
429 round_start = odhcp6c_get_milli_time();
430 elapsed = round_start - start;
431 syslog(LOG_NOTICE, "Got a valid reply after "
432 "%ums", (unsigned)elapsed);
434 if (retx->handler_reply)
435 len = retx->handler_reply(
438 if (round_end - round_start > 1000)
439 round_end = 1000 + round_start;
444 if (retx->handler_finish)
445 len = retx->handler_finish();
446 } while (len < 0 && elapsed / 1000 < timeout);
452 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
453 const uint8_t transaction[3], enum dhcpv6_msg type)
455 const struct dhcpv6_header *rep = buf;
456 if (len < (ssize_t)sizeof(*rep) || memcmp(rep->tr_id,
457 transaction, sizeof(rep->tr_id)))
458 return false; // Invalid reply
460 if (type == DHCPV6_MSG_SOLICIT) {
461 if (rep->msg_type != DHCPV6_MSG_ADVERT &&
462 rep->msg_type != DHCPV6_MSG_REPLY)
464 } else if (type == DHCPV6_MSG_UNKNOWN) {
465 if (!accept_reconfig || rep->msg_type != DHCPV6_MSG_RECONF)
467 } else if (rep->msg_type != DHCPV6_MSG_REPLY) {
471 uint8_t *end = ((uint8_t*)buf) + len, *odata;
472 uint16_t otype, olen;
473 bool clientid_ok = false, serverid_ok = false;
475 size_t client_id_len, server_id_len;
476 void *client_id = odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
477 void *server_id = odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
479 dhcpv6_for_each_option(&rep[1], end, otype, olen, odata)
480 if (otype == DHCPV6_OPT_CLIENTID)
481 clientid_ok = (olen + 4U == client_id_len) && !memcmp(
482 &odata[-4], client_id, client_id_len);
483 else if (otype == DHCPV6_OPT_SERVERID)
484 serverid_ok = (olen + 4U == server_id_len) && !memcmp(
485 &odata[-4], server_id, server_id_len);
487 return clientid_ok && (serverid_ok || server_id_len == 0);
491 int dhcpv6_poll_reconfigure(void)
493 int ret = dhcpv6_request(DHCPV6_MSG_UNKNOWN);
495 ret = dhcpv6_request(ret);
501 static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig,
502 const void *opt, const void *end)
504 // TODO: should verify the reconfigure message
505 uint16_t otype, olen;
506 uint8_t *odata, msg = DHCPV6_MSG_RENEW;
507 dhcpv6_for_each_option(opt, end, otype, olen, odata)
508 if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1 && (
509 odata[0] == DHCPV6_MSG_RENEW ||
510 odata[0] == DHCPV6_MSG_INFO_REQ))
513 dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL);
518 // Collect all advertised servers
519 static int dhcpv6_handle_advert(_unused enum dhcpv6_msg orig,
520 const void *opt, const void *end)
522 uint16_t olen, otype;
524 struct dhcpv6_server_cand cand = {false, false, 0, 0, {0}};
526 dhcpv6_for_each_option(opt, end, otype, olen, odata) {
527 if (otype == DHCPV6_OPT_SERVERID && olen <= 130) {
528 memcpy(cand.duid, odata, olen);
529 cand.duid_len = olen;
530 } else if (otype == DHCPV6_OPT_STATUS && olen >= 2 && !odata[0]
531 && odata[1] == DHCPV6_NoAddrsAvail) {
532 if (na_mode == IA_MODE_FORCE) {
535 cand.has_noaddravail = true;
536 cand.preference -= 1000;
538 } else if (otype == DHCPV6_OPT_STATUS && olen >= 2 && !odata[0]
539 && odata[1] == DHCPV6_NoPrefixAvail) {
540 cand.preference -= 2000;
541 } else if (otype == DHCPV6_OPT_PREF && olen >= 1 &&
542 cand.preference >= 0) {
543 cand.preference = odata[0];
544 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
545 cand.wants_reconfigure = true;
546 } else if (otype == DHCPV6_OPT_IA_PD && request_prefix) {
547 struct dhcpv6_ia_hdr *h = (void*)odata;
548 uint8_t *oend = odata + olen, *d;
549 dhcpv6_for_each_option(&h[1], oend, otype, olen, d) {
550 if (otype == DHCPV6_OPT_IA_PREFIX)
551 cand.preference += 2000;
552 else if (otype == DHCPV6_OPT_STATUS &&
553 olen >= 2 && d[0] == 0 &&
554 d[1] == DHCPV6_NoPrefixAvail)
555 cand.preference -= 2000;
560 if (cand.duid_len > 0)
561 odhcp6c_add_state(STATE_SERVER_CAND, &cand, sizeof(cand));
567 static int dhcpv6_commit_advert(void)
570 struct dhcpv6_server_cand *c = NULL, *cand =
571 odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
574 for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
575 if (cand[i].has_noaddravail)
576 retry = true; // We want to try again
578 if (!c || c->preference < cand[i].preference)
582 if (retry && na_mode == IA_MODE_TRY) {
583 // We give it a second try without the IA_NA
584 na_mode = IA_MODE_NONE;
585 return dhcpv6_request(DHCPV6_MSG_SOLICIT);
589 uint16_t hdr[2] = {htons(DHCPV6_OPT_SERVERID),
591 odhcp6c_add_state(STATE_SERVER_ID, hdr, sizeof(hdr));
592 odhcp6c_add_state(STATE_SERVER_ID, c->duid, c->duid_len);
593 accept_reconfig = c->wants_reconfigure;
596 odhcp6c_clear_state(STATE_SERVER_CAND);
600 else if (request_prefix || na_mode != IA_MODE_NONE)
601 return DHCPV6_STATEFUL;
603 return DHCPV6_STATELESS;
607 static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig,
608 const void *opt, const void *end)
610 dhcpv6_handle_advert(orig, opt, end);
611 if (dhcpv6_commit_advert() < 0) {
612 dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, NULL, NULL);
616 return dhcpv6_handle_reply(orig, opt, end);
620 static int dhcpv6_handle_reply(enum dhcpv6_msg orig,
621 const void *opt, const void *end)
624 uint16_t otype, olen;
626 static time_t last_update = 0;
627 time_t now = odhcp6c_get_milli_time() / 1000;
629 uint32_t elapsed = now - last_update;
632 if (orig == DHCPV6_MSG_UNKNOWN) {
646 t1 = t2 = t3 = UINT32_MAX;
650 odhcp6c_clear_state(STATE_DNS);
651 odhcp6c_clear_state(STATE_SEARCH);
652 odhcp6c_clear_state(STATE_SNTP_IP);
653 odhcp6c_clear_state(STATE_SNTP_FQDN);
654 odhcp6c_clear_state(STATE_SIP_IP);
655 odhcp6c_clear_state(STATE_SIP_FQDN);
658 // Parse and find all matching IAs
659 dhcpv6_for_each_option(opt, end, otype, olen, odata) {
660 if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)
661 && olen > sizeof(struct dhcpv6_ia_hdr)) {
662 struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
663 uint32_t l_t1 = ntohl(ia_hdr->t1);
664 uint32_t l_t2 = ntohl(ia_hdr->t2);
666 // Test ID and T1-T2 validity
667 if (ia_hdr->iaid != 1 || l_t2 < l_t1)
671 uint16_t stype, slen;
673 // Test status and bail if error
674 dhcpv6_for_each_option(&ia_hdr[1], odata + olen,
676 if (stype == DHCPV6_OPT_STATUS && slen >= 2 &&
677 (sdata[0] || sdata[1]))
684 if (l_t1 > 0 && t1 > l_t1)
687 if (l_t2 > 0 && t2 > l_t2)
690 uint32_t n = dhcpv6_parse_ia(&ia_hdr[1], odata + olen);
707 } else if (otype == DHCPV6_OPT_DNS_SERVERS) {
709 odhcp6c_add_state(STATE_DNS, odata, olen);
710 } else if (otype == DHCPV6_OPT_DNS_DOMAIN) {
711 odhcp6c_add_state(STATE_SEARCH, odata, olen);
712 } else if (otype == DHCPV6_OPT_NTP_SERVER) {
713 uint16_t stype, slen;
715 // Test status and bail if error
716 dhcpv6_for_each_option(odata, odata + olen,
717 stype, slen, sdata) {
718 if (slen == 16 && (stype == NTP_MC_ADDR ||
719 stype == NTP_SRV_ADDR))
720 odhcp6c_add_state(STATE_SNTP_IP,
722 else if (slen > 0 && stype == NTP_SRV_FQDN)
723 odhcp6c_add_state(STATE_SNTP_FQDN,
726 } else if (otype == DHCPV6_OPT_SIP_SERVER_A) {
728 odhcp6c_add_state(STATE_SIP_IP, odata, olen);
729 } else if (otype == DHCPV6_OPT_SIP_SERVER_D) {
730 odhcp6c_add_state(STATE_SIP_FQDN, odata, olen);
731 } else if (otype == DHCPV6_OPT_INFO_REFRESH && olen >= 4) {
732 uint32_t refresh = ntohl(*((uint32_t*)odata));
733 if (refresh < (uint32_t)t1)
735 } else if (otype != DHCPV6_OPT_CLIENTID &&
736 otype != DHCPV6_OPT_SERVERID) {
737 odhcp6c_add_state(STATE_CUSTOM_OPTS,
738 &odata[-4], olen + 4);
746 static uint32_t dhcpv6_parse_ia(void *opt, void *end)
748 uint32_t timeout = UINT32_MAX; // Minimum timeout
749 uint16_t otype, olen;
752 struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT,
753 0, 0, IN6ADDR_ANY_INIT, 0, 0};
756 dhcpv6_for_each_option(opt, end, otype, olen, odata) {
757 if (otype == DHCPV6_OPT_IA_PREFIX) {
758 struct dhcpv6_ia_prefix *prefix = (void*)&odata[-4];
759 if (olen + 4U < sizeof(*prefix))
762 entry.valid = ntohl(prefix->valid);
763 entry.preferred = ntohl(prefix->preferred);
765 if (entry.preferred > entry.valid)
768 entry.length = prefix->prefix;
769 entry.target = prefix->addr;
773 uint16_t stype, slen;
775 dhcpv6_for_each_option(odata + sizeof(*prefix) - 4U,
776 odata + olen, stype, slen, sdata) {
777 if (stype != DHCPV6_OPT_PD_EXCLUDE || slen < 2)
780 uint8_t elen = sdata[0];
784 if (elen <= 32 || elen <= entry.length) {
790 uint8_t bytes = ((elen - entry.length - 1) / 8) + 1;
796 uint32_t exclude = 0;
798 exclude = exclude << 8 | sdata[bytes];
801 exclude >>= 8 - ((elen - entry.length) % 8);
802 exclude <<= 64 - elen;
804 // Abusing router & priority fields for exclusion
805 entry.router = entry.target;
806 entry.router.s6_addr32[1] |= htonl(exclude);
807 entry.priority = elen;
811 odhcp6c_update_entry(STATE_IA_PD, &entry);
814 memset(&entry.router, 0, sizeof(entry.router));
815 } else if (otype == DHCPV6_OPT_IA_ADDR) {
816 struct dhcpv6_ia_addr *addr = (void*)&odata[-4];
817 if (olen + 4U < sizeof(*addr))
820 entry.preferred = ntohl(addr->preferred);
821 entry.valid = ntohl(addr->valid);
823 if (entry.preferred > entry.valid)
827 entry.target = addr->addr;
829 odhcp6c_update_entry(STATE_IA_NA, &entry);
832 if (entry.valid > 0 && timeout > entry.valid)
833 timeout = entry.valid;