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>
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
46 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
47 const uint8_t transaction[3], enum dhcpv6_msg type);
49 static uint32_t dhcpv6_parse_ia(void *opt, void *end);
51 static reply_handler dhcpv6_handle_reply;
52 static reply_handler dhcpv6_handle_advert;
53 static reply_handler dhcpv6_handle_rebind_reply;
54 static reply_handler dhcpv6_handle_reconfigure;
55 static int dhcpv6_commit_advert(void);
59 // RFC 3315 - 5.5 Timeout and Delay values
60 static struct dhcpv6_retx dhcpv6_retx[_DHCPV6_MSG_MAX] = {
61 [DHCPV6_MSG_UNKNOWN] = {false, 1, 120, 0, "<POLL>",
62 dhcpv6_handle_reconfigure, NULL},
63 [DHCPV6_MSG_SOLICIT] = {true, 1, 3600, 0, "SOLICIT",
64 dhcpv6_handle_advert, dhcpv6_commit_advert},
65 [DHCPV6_MSG_REQUEST] = {true, 1, 30, 10, "REQUEST",
66 dhcpv6_handle_reply, NULL},
67 [DHCPV6_MSG_RENEW] = {false, 10, 600, 0, "RENEW",
68 dhcpv6_handle_reply, NULL},
69 [DHCPV6_MSG_REBIND] = {false, 10, 600, 0, "REBIND",
70 dhcpv6_handle_rebind_reply, NULL},
71 [DHCPV6_MSG_RELEASE] = {false, 1, 0, 5, "RELEASE", NULL, NULL},
72 [DHCPV6_MSG_DECLINE] = {false, 1, 0, 5, "DECLINE", NULL, NULL},
73 [DHCPV6_MSG_INFO_REQ] = {true, 1, 120, 0, "INFOREQ",
74 dhcpv6_handle_reply, NULL},
80 static int ifindex = -1;
81 static int64_t t1 = 0, t2 = 0, t3 = 0;
84 static int request_prefix = -1;
85 static enum odhcp6c_ia_mode na_mode = IA_MODE_NONE, pd_mode = IA_MODE_NONE;
86 static bool accept_reconfig = false;
89 static uint8_t reconf_key[16];
93 int init_dhcpv6(const char *ifname, int request_pd, int sol_timeout)
95 request_prefix = request_pd;
96 dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = sol_timeout;
98 sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
102 strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
103 if (ioctl(sock, SIOCGIFINDEX, &ifr))
105 ifindex = ifr.ifr_ifindex;
107 // Create client DUID
108 size_t client_id_len;
109 odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
110 if (client_id_len == 0) {
111 ioctl(sock, SIOCGIFHWADDR, &ifr);
112 uint8_t duid[14] = {0, DHCPV6_OPT_CLIENTID, 0, 10, 0,
113 DHCPV6_DUID_LLADDR, 0, 1};
114 memcpy(&duid[8], ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
116 uint8_t zero[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
117 struct ifreq ifs[100], *ifp, *ifend;
120 ifc.ifc_len = sizeof(ifs);
122 if (!memcmp(&duid[8], zero, ETHER_ADDR_LEN) &&
123 ioctl(sock, SIOCGIFCONF, &ifc) >= 0) {
124 // If our interface doesn't have an address...
125 ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq));
126 for (ifp = ifc.ifc_req; ifp < ifend &&
127 !memcmp(&duid[8], zero, 6); ifp++) {
128 memcpy(ifr.ifr_name, ifp->ifr_name,
129 sizeof(ifr.ifr_name));
130 ioctl(sock, SIOCGIFHWADDR, &ifr);
131 memcpy(&duid[8], ifr.ifr_hwaddr.sa_data,
136 odhcp6c_add_state(STATE_CLIENT_ID, duid, sizeof(duid));
141 htons(DHCPV6_OPT_SIP_SERVER_D),
142 htons(DHCPV6_OPT_SIP_SERVER_A),
143 htons(DHCPV6_OPT_DNS_SERVERS),
144 htons(DHCPV6_OPT_DNS_DOMAIN),
145 htons(DHCPV6_OPT_NTP_SERVER),
146 htons(DHCPV6_OPT_SIP_SERVER_A),
147 htons(DHCPV6_OPT_AFTR_NAME),
148 htons(DHCPV6_OPT_PD_EXCLUDE),
149 #ifdef EXT_PREFIX_CLASS
150 htons(DHCPV6_OPT_PREFIX_CLASS),
153 odhcp6c_add_state(STATE_ORO, oro, sizeof(oro));
156 // Configure IPv6-options
158 setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val));
159 setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
161 setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &val, sizeof(val));
162 setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
164 struct sockaddr_in6 client_addr = { .sin6_family = AF_INET6,
165 .sin6_port = htons(DHCPV6_CLIENT_PORT), .sin6_flowinfo = 0 };
166 if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr)))
173 void dhcpv6_set_ia_mode(enum odhcp6c_ia_mode na, enum odhcp6c_ia_mode pd)
180 static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
184 gethostname(fqdn_buf, sizeof(fqdn_buf));
191 size_t fqdn_len = 5 + dn_comp(fqdn_buf, fqdn.data,
192 sizeof(fqdn.data), NULL, NULL);
193 fqdn.type = htons(DHCPV6_OPT_FQDN);
194 fqdn.len = htons(fqdn_len - 4);
200 void *cl_id = odhcp6c_get_state(STATE_CLIENT_ID, &cl_id_len);
204 void *srv_id = odhcp6c_get_state(STATE_SERVER_ID, &srv_id_len);
207 size_t ia_pd_entries, ia_pd_len = 0;
208 struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
209 ia_pd_entries /= sizeof(*e);
210 struct dhcpv6_ia_hdr hdr_ia_pd = {
211 htons(DHCPV6_OPT_IA_PD),
212 htons(sizeof(hdr_ia_pd) - 4),
217 uint8_t *ia_pd = alloca(ia_pd_entries * (sizeof(struct dhcpv6_ia_prefix) + 10));
218 for (size_t i = 0; i < ia_pd_entries; ++i) {
220 if (e[i].priority > 0)
221 ex_len = ((e[i].priority - e[i].length - 1) / 8) + 6;
223 struct dhcpv6_ia_prefix p = {
224 .type = htons(DHCPV6_OPT_IA_PREFIX),
225 .len = htons(sizeof(p) - 4U + ex_len),
226 .prefix = e[i].length,
230 memcpy(ia_pd + ia_pd_len, &p, sizeof(p));
231 ia_pd_len += sizeof(p);
234 ia_pd[ia_pd_len++] = 0;
235 ia_pd[ia_pd_len++] = DHCPV6_OPT_PD_EXCLUDE;
236 ia_pd[ia_pd_len++] = 0;
237 ia_pd[ia_pd_len++] = ex_len - 4;
238 ia_pd[ia_pd_len++] = e[i].priority;
240 uint32_t excl = ntohl(e[i].router.s6_addr32[1]);
241 excl >>= (64 - e[i].priority);
242 excl <<= 8 - ((e[i].priority - e[i].length) % 8);
244 for (size_t i = ex_len - 5; i > 0; --i, excl >>= 8)
245 ia_pd[ia_pd_len + i] = excl & 0xff;
246 ia_pd_len += ex_len - 5;
250 struct dhcpv6_ia_prefix pref = {
251 .type = htons(DHCPV6_OPT_IA_PREFIX),
252 .len = htons(25), .prefix = request_prefix
254 if (request_prefix > 0 && ia_pd_len == 0 && type == DHCPV6_MSG_SOLICIT) {
255 ia_pd = (uint8_t*)&pref;
256 ia_pd_len = sizeof(pref);
258 hdr_ia_pd.len = htons(ntohs(hdr_ia_pd.len) + ia_pd_len);
261 size_t ia_na_entries, ia_na_len = 0;
263 e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
264 ia_na_entries /= sizeof(*e);
266 struct dhcpv6_ia_hdr hdr_ia_na = {
267 htons(DHCPV6_OPT_IA_NA),
268 htons(sizeof(hdr_ia_na) - 4),
272 struct dhcpv6_ia_addr pa[ia_na_entries];
273 for (size_t i = 0; i < ia_na_entries; ++i) {
274 pa[i].type = htons(DHCPV6_OPT_IA_ADDR);
275 pa[i].len = htons(sizeof(pa[i]) - 4U);
276 pa[i].addr = e[i].target;
282 ia_na_len = sizeof(pa);
283 hdr_ia_na.len = htons(ntohs(hdr_ia_na.len) + ia_na_len);
285 // Reconfigure Accept
289 } reconf_accept = {htons(DHCPV6_OPT_RECONF_ACCEPT), 0};
291 // Request Information Refresh
292 uint16_t oro_refresh = htons(DHCPV6_OPT_INFO_REFRESH);
296 void *oro = odhcp6c_get_state(STATE_ORO, &oro_len);
300 uint16_t elapsed_type;
301 uint16_t elapsed_len;
302 uint16_t elapsed_value;
306 type, {trid[0], trid[1], trid[2]},
307 htons(DHCPV6_OPT_ELAPSED), htons(2),
308 htons((ecs > 0xffff) ? 0xffff : ecs),
309 htons(DHCPV6_OPT_ORO), htons(oro_len),
312 struct iovec iov[] = {
317 {srv_id, srv_id_len},
318 {&reconf_accept, sizeof(reconf_accept)},
320 {&hdr_ia_na, sizeof(hdr_ia_na)},
322 {&hdr_ia_pd, sizeof(hdr_ia_pd)},
326 size_t cnt = ARRAY_SIZE(iov);
327 if (type == DHCPV6_MSG_INFO_REQ) {
329 iov[2].iov_len = sizeof(oro_refresh);
330 hdr.oro_len = htons(oro_len + sizeof(oro_refresh));
331 } else if (!request_prefix) {
335 // Disable IAs if not used
336 if (type != DHCPV6_MSG_SOLICIT) {
344 if (na_mode == IA_MODE_NONE)
347 struct sockaddr_in6 srv = {AF_INET6, htons(DHCPV6_SERVER_PORT),
348 0, ALL_DHCPV6_RELAYS, ifindex};
349 struct msghdr msg = {&srv, sizeof(srv), iov, cnt, NULL, 0, 0};
351 sendmsg(sock, &msg, 0);
355 static int64_t dhcpv6_rand_delay(int64_t time)
358 odhcp6c_random(&random, sizeof(random));
359 return (time * ((int64_t)random % 1000LL)) / 10000LL;
363 int dhcpv6_request(enum dhcpv6_msg type)
365 uint8_t buf[1536], rc = 0;
366 uint64_t timeout = UINT32_MAX;
367 struct dhcpv6_retx *retx = &dhcpv6_retx[type];
370 struct timespec ts = {0, 0};
371 ts.tv_nsec = dhcpv6_rand_delay(10 * DHCPV6_REQ_DELAY);
372 nanosleep(&ts, NULL);
375 if (type == DHCPV6_MSG_UNKNOWN)
377 else if (type == DHCPV6_MSG_RENEW)
378 timeout = (t2 > t1) ? t2 - t1 : 0;
379 else if (type == DHCPV6_MSG_REBIND)
380 timeout = (t3 > t2) ? t3 - t2 : 0;
385 syslog(LOG_NOTICE, "Starting %s transaction (timeout %llus, max rc %d)", retx->name, timeout, retx->max_rc);
387 uint64_t start = odhcp6c_get_milli_time(), round_start = start, elapsed;
389 // Generate transaction ID
390 uint8_t trid[3] = {0, 0, 0};
391 if (type != DHCPV6_MSG_UNKNOWN)
392 odhcp6c_random(trid, sizeof(trid));
398 int64_t delay = dhcpv6_rand_delay(retx->init_timeo * 1000);
400 // First RT MUST be strictly greater than IRT for solicit messages (RFC3313 17.1.2)
401 while (type == DHCPV6_MSG_SOLICIT && delay <= 0)
402 delay = dhcpv6_rand_delay(retx->init_timeo * 1000);
404 rto = (retx->init_timeo * 1000 + delay);
407 rto = (2 * rto + dhcpv6_rand_delay(rto));
409 if (retx->max_timeo && (rto >= retx->max_timeo * 1000))
410 rto = retx->max_timeo * 1000 +
411 dhcpv6_rand_delay(retx->max_timeo * 1000);
413 // Calculate end for this round and elapsed time
414 uint64_t round_end = round_start + rto;
415 elapsed = round_start - start;
417 // Don't wait too long
418 if (round_end - start > timeout * 1000)
419 round_end = timeout * 1000 + start;
421 // Built and send package
422 if (type != DHCPV6_MSG_UNKNOWN) {
423 syslog(LOG_NOTICE, "Send %s message (elapsed %llums, rc %d)", retx->name, elapsed, rc);
424 dhcpv6_send(type, trid, elapsed / 10);
429 for (; len < 0 && round_start < round_end;
430 round_start = odhcp6c_get_milli_time()) {
431 // Check for pending signal
432 if (odhcp6c_signal_process())
435 // Set timeout for receiving
436 uint64_t t = round_end - round_start;
437 struct timeval timeout = {t / 1000, (t % 1000) * 1000};
438 setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO,
439 &timeout, sizeof(timeout));
442 len = recv(sock, buf, sizeof(buf), 0);
444 if (!dhcpv6_response_is_valid(buf, len, trid, type))
448 uint8_t *opt = &buf[4];
449 uint8_t *opt_end = opt + len - 4;
451 round_start = odhcp6c_get_milli_time();
452 elapsed = round_start - start;
453 syslog(LOG_NOTICE, "Got a valid reply after "
456 if (retx->handler_reply)
457 len = retx->handler_reply(
458 type, rc, opt, opt_end);
460 if (len > 0 && round_end - round_start > 1000)
461 round_end = 1000 + round_start;
466 if (retx->handler_finish)
467 len = retx->handler_finish();
468 } while (len < 0 && ((elapsed / 1000 < timeout) && (!retx->max_rc || rc < retx->max_rc)));
474 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
475 const uint8_t transaction[3], enum dhcpv6_msg type)
477 const struct dhcpv6_header *rep = buf;
478 if (len < (ssize_t)sizeof(*rep) || memcmp(rep->tr_id,
479 transaction, sizeof(rep->tr_id)))
480 return false; // Invalid reply
482 if (type == DHCPV6_MSG_SOLICIT) {
483 if (rep->msg_type != DHCPV6_MSG_ADVERT &&
484 rep->msg_type != DHCPV6_MSG_REPLY)
486 } else if (type == DHCPV6_MSG_UNKNOWN) {
487 if (!accept_reconfig || rep->msg_type != DHCPV6_MSG_RECONF)
489 } else if (rep->msg_type != DHCPV6_MSG_REPLY) {
493 uint8_t *end = ((uint8_t*)buf) + len, *odata;
494 uint16_t otype, olen;
495 bool clientid_ok = false, serverid_ok = false, rcauth_ok = false;
497 size_t client_id_len, server_id_len;
498 void *client_id = odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
499 void *server_id = odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
501 dhcpv6_for_each_option(&rep[1], end, otype, olen, odata) {
502 if (otype == DHCPV6_OPT_CLIENTID) {
503 clientid_ok = (olen + 4U == client_id_len) && !memcmp(
504 &odata[-4], client_id, client_id_len);
505 } else if (otype == DHCPV6_OPT_SERVERID) {
506 serverid_ok = (olen + 4U == server_id_len) && !memcmp(
507 &odata[-4], server_id, server_id_len);
508 } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
509 sizeof(struct dhcpv6_auth_reconfigure)) {
510 struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
511 if (r->protocol != 3 || r->algorithm != 1 || r->reconf_type != 2)
515 uint8_t serverhash[16], secretbytes[16], hash[16];
516 memcpy(serverhash, r->key, sizeof(serverhash));
517 memset(r->key, 0, sizeof(r->key));
518 memcpy(secretbytes, reconf_key, sizeof(secretbytes));
520 for (size_t i = 0; i < sizeof(secretbytes); ++i)
521 secretbytes[i] ^= 0x36;
524 md5_append(&md5, secretbytes, sizeof(secretbytes));
525 md5_append(&md5, buf, len);
526 md5_finish(&md5, hash);
528 for (size_t i = 0; i < sizeof(secretbytes); ++i) {
529 secretbytes[i] ^= 0x36;
530 secretbytes[i] ^= 0x5c;
534 md5_append(&md5, secretbytes, sizeof(secretbytes));
535 md5_append(&md5, hash, 16);
536 md5_finish(&md5, hash);
538 rcauth_ok = !memcmp(hash, serverhash, sizeof(hash));
542 if (rep->msg_type == DHCPV6_MSG_RECONF && !rcauth_ok)
545 return clientid_ok && (serverid_ok || server_id_len == 0);
549 int dhcpv6_poll_reconfigure(void)
551 int ret = dhcpv6_request(DHCPV6_MSG_UNKNOWN);
553 ret = dhcpv6_request(ret);
559 static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig, const int rc,
560 const void *opt, const void *end)
562 // TODO: should verify the reconfigure message
563 uint16_t otype, olen;
564 uint8_t *odata, msg = DHCPV6_MSG_RENEW;
565 dhcpv6_for_each_option(opt, end, otype, olen, odata)
566 if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1 && (
567 odata[0] == DHCPV6_MSG_RENEW ||
568 odata[0] == DHCPV6_MSG_INFO_REQ))
571 dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, rc, NULL, NULL);
576 // Collect all advertised servers
577 static int dhcpv6_handle_advert(enum dhcpv6_msg orig, const int rc,
578 const void *opt, const void *end)
580 uint16_t olen, otype;
581 uint8_t *odata, pref = 0;
582 struct dhcpv6_server_cand cand = {false, false, 0, 0, {0}, NULL, NULL, 0, 0};
583 bool have_na = false;
586 dhcpv6_for_each_option(opt, end, otype, olen, odata) {
587 if (orig == DHCPV6_MSG_SOLICIT &&
588 (otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA) &&
589 olen > sizeof(struct dhcpv6_ia_hdr)) {
590 struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
591 dhcpv6_parse_ia(&ia_hdr[1], odata + olen);
594 if (otype == DHCPV6_OPT_SERVERID && olen <= 130) {
595 memcpy(cand.duid, odata, olen);
596 cand.duid_len = olen;
597 } else if (otype == DHCPV6_OPT_STATUS && olen >= 2) {
598 int error = ((int)odata[0] << 8 | (int)odata[1]);
601 case DHCPV6_NoPrefixAvail:
602 // Status code on global level
603 if (pd_mode == IA_MODE_FORCE)
605 cand.preference -= 2000;
608 case DHCPV6_NoAddrsAvail:
609 // Status code on global level
610 if (na_mode == IA_MODE_FORCE)
617 } else if (otype == DHCPV6_OPT_PREF && olen >= 1 &&
618 cand.preference >= 0) {
619 cand.preference = pref = odata[0];
620 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
621 cand.wants_reconfigure = true;
622 } else if (otype == DHCPV6_OPT_IA_PD && request_prefix) {
623 struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
624 uint8_t *oend = odata + olen, *d;
625 dhcpv6_for_each_option(&h[1], oend, otype, olen, d) {
626 if (otype == DHCPV6_OPT_IA_PREFIX && (olen + 4) >=
627 (uint16_t)sizeof(struct dhcpv6_ia_prefix)) {
628 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&d[-4];
632 } else if (otype == DHCPV6_OPT_IA_NA) {
633 struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
634 uint8_t *oend = odata + olen, *d;
635 dhcpv6_for_each_option(&h[1], oend, otype, olen, d)
636 if (otype == DHCPV6_OPT_IA_ADDR)
641 if ((!have_na && na_mode == IA_MODE_FORCE) ||
642 (!have_pd && pd_mode == IA_MODE_FORCE))
645 if (na_mode != IA_MODE_NONE && !have_na) {
646 cand.has_noaddravail = true;
647 cand.preference -= 1000;
650 if (pd_mode != IA_MODE_NONE) {
652 cand.preference += 2000 + (128 - have_pd);
654 cand.preference -= 2000;
657 if (cand.duid_len > 0) {
658 cand.ia_na = odhcp6c_move_state(STATE_IA_NA, &cand.ia_na_len);
659 cand.ia_pd = odhcp6c_move_state(STATE_IA_PD, &cand.ia_pd_len);
660 odhcp6c_add_state(STATE_SERVER_CAND, &cand, sizeof(cand));
663 if (orig == DHCPV6_MSG_SOLICIT) {
664 odhcp6c_clear_state(STATE_IA_NA);
665 odhcp6c_clear_state(STATE_IA_PD);
668 return (rc > 1 || (pref == 255 && cand.preference > 0)) ? 1 : -1;
672 static int dhcpv6_commit_advert(void)
675 struct dhcpv6_server_cand *c = NULL, *cand =
676 odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
679 for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
680 if (cand[i].has_noaddravail)
681 retry = true; // We want to try again
683 if (!c || c->preference < cand[i].preference)
687 if (retry && na_mode == IA_MODE_TRY) {
688 // We give it a second try without the IA_NA
689 na_mode = IA_MODE_NONE;
690 return dhcpv6_request(DHCPV6_MSG_SOLICIT);
694 uint16_t hdr[2] = {htons(DHCPV6_OPT_SERVERID),
696 odhcp6c_add_state(STATE_SERVER_ID, hdr, sizeof(hdr));
697 odhcp6c_add_state(STATE_SERVER_ID, c->duid, c->duid_len);
698 accept_reconfig = c->wants_reconfigure;
700 odhcp6c_add_state(STATE_IA_NA, c->ia_na, c->ia_na_len);
702 odhcp6c_add_state(STATE_IA_PD, c->ia_pd, c->ia_pd_len);
705 for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
709 odhcp6c_clear_state(STATE_SERVER_CAND);
713 else if ((request_prefix && c->ia_pd_len) || (na_mode != IA_MODE_NONE && c->ia_na_len))
714 return DHCPV6_STATEFUL;
716 return DHCPV6_STATELESS;
720 static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig, const int rc,
721 const void *opt, const void *end)
723 dhcpv6_handle_advert(orig, rc, opt, end);
724 if (dhcpv6_commit_advert() < 0) {
725 dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, rc, NULL, NULL);
729 return dhcpv6_handle_reply(orig, rc, opt, end);
733 static int dhcpv6_handle_reply(enum dhcpv6_msg orig, _unused const int rc,
734 const void *opt, const void *end)
737 uint16_t otype, olen;
741 if (orig == DHCPV6_MSG_UNKNOWN) {
742 static time_t last_update = 0;
743 time_t now = odhcp6c_get_milli_time() / 1000;
745 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
761 t1 = t2 = t3 = UINT32_MAX;
764 if (orig == DHCPV6_MSG_REQUEST) {
765 // Delete NA and PD we have in the state from the Advert
766 odhcp6c_clear_state(STATE_IA_NA);
767 odhcp6c_clear_state(STATE_IA_PD);
771 odhcp6c_clear_state(STATE_DNS);
772 odhcp6c_clear_state(STATE_SEARCH);
773 odhcp6c_clear_state(STATE_SNTP_IP);
774 odhcp6c_clear_state(STATE_SNTP_FQDN);
775 odhcp6c_clear_state(STATE_SIP_IP);
776 odhcp6c_clear_state(STATE_SIP_FQDN);
777 odhcp6c_clear_state(STATE_AFTR_NAME);
780 // Parse and find all matching IAs
781 dhcpv6_for_each_option(opt, end, otype, olen, odata) {
782 if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)
783 && olen > sizeof(struct dhcpv6_ia_hdr)) {
784 struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
785 uint32_t l_t1 = ntohl(ia_hdr->t1);
786 uint32_t l_t2 = ntohl(ia_hdr->t2);
788 // Test ID and T1-T2 validity
789 if (ia_hdr->iaid != 1 || l_t2 < l_t1)
793 uint16_t stype, slen;
795 // Test status and bail if error
796 dhcpv6_for_each_option(&ia_hdr[1], odata + olen,
798 if (stype == DHCPV6_OPT_STATUS && slen >= 2)
799 error = ((int)sdata[0]) << 8 | ((int)sdata[1]);
802 syslog(LOG_WARNING, "Server returned IAID status %i!", error);
808 uint32_t n = dhcpv6_parse_ia(&ia_hdr[1], odata + olen);
820 if (l_t1 > 0 && t1 > l_t1)
823 if (l_t2 > 0 && t2 > l_t2)
826 } else if (otype == DHCPV6_OPT_DNS_SERVERS) {
828 odhcp6c_add_state(STATE_DNS, odata, olen);
829 } else if (otype == DHCPV6_OPT_DNS_DOMAIN) {
830 odhcp6c_add_state(STATE_SEARCH, odata, olen);
831 } else if (otype == DHCPV6_OPT_NTP_SERVER) {
832 uint16_t stype, slen;
834 // Test status and bail if error
835 dhcpv6_for_each_option(odata, odata + olen,
836 stype, slen, sdata) {
837 if (slen == 16 && (stype == NTP_MC_ADDR ||
838 stype == NTP_SRV_ADDR))
839 odhcp6c_add_state(STATE_SNTP_IP,
841 else if (slen > 0 && stype == NTP_SRV_FQDN)
842 odhcp6c_add_state(STATE_SNTP_FQDN,
845 } else if (otype == DHCPV6_OPT_SIP_SERVER_A) {
847 odhcp6c_add_state(STATE_SIP_IP, odata, olen);
848 } else if (otype == DHCPV6_OPT_SIP_SERVER_D) {
849 odhcp6c_add_state(STATE_SIP_FQDN, odata, olen);
850 } else if (otype == DHCPV6_OPT_INFO_REFRESH && olen >= 4) {
851 uint32_t refresh = ntohl(*((uint32_t*)odata));
852 if (refresh < (uint32_t)t1)
854 } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
855 sizeof(struct dhcpv6_auth_reconfigure)) {
856 struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
857 if (r->protocol == 3 && r->algorithm == 1 &&
859 memcpy(reconf_key, r->key, sizeof(r->key));
860 } else if (otype == DHCPV6_OPT_AFTR_NAME && olen > 3) {
862 odhcp6c_get_state(STATE_AFTR_NAME, &cur_len);
864 odhcp6c_add_state(STATE_AFTR_NAME, odata, olen);
865 } else if (otype != DHCPV6_OPT_CLIENTID &&
866 otype != DHCPV6_OPT_SERVERID) {
867 odhcp6c_add_state(STATE_CUSTOM_OPTS,
868 &odata[-4], olen + 4);
872 if (t1 == UINT32_MAX)
875 if (t2 == UINT32_MAX)
878 if (t3 == UINT32_MAX)
885 static uint32_t dhcpv6_parse_ia(void *opt, void *end)
887 uint32_t timeout = UINT32_MAX; // Minimum timeout
888 uint16_t otype, olen;
892 dhcpv6_for_each_option(opt, end, otype, olen, odata) {
893 struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0,
894 IN6ADDR_ANY_INIT, 0, 0, 0};
896 if (otype == DHCPV6_OPT_IA_PREFIX) {
897 struct dhcpv6_ia_prefix *prefix = (void*)&odata[-4];
898 if (olen + 4U < sizeof(*prefix))
901 entry.valid = ntohl(prefix->valid);
902 entry.preferred = ntohl(prefix->preferred);
904 if (entry.preferred > entry.valid)
907 entry.length = prefix->prefix;
908 entry.target = prefix->addr;
909 uint16_t stype, slen;
912 #ifdef EXT_PREFIX_CLASS
913 // Find prefix class, if any
914 dhcpv6_for_each_option(&prefix[1], odata + olen,
916 if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
917 entry.class = sdata[0] << 8 | sdata[1];
922 dhcpv6_for_each_option(odata + sizeof(*prefix) - 4U,
923 odata + olen, stype, slen, sdata) {
924 if (stype != DHCPV6_OPT_PD_EXCLUDE || slen < 2)
927 uint8_t elen = sdata[0];
931 if (elen <= 32 || elen <= entry.length) {
937 uint8_t bytes = ((elen - entry.length - 1) / 8) + 1;
943 uint32_t exclude = 0;
945 exclude = exclude << 8 | sdata[bytes];
948 exclude >>= 8 - ((elen - entry.length) % 8);
949 exclude <<= 64 - elen;
951 // Abusing router & priority fields for exclusion
952 entry.router = entry.target;
953 entry.router.s6_addr32[1] |= htonl(exclude);
954 entry.priority = elen;
958 odhcp6c_update_entry(STATE_IA_PD, &entry);
961 memset(&entry.router, 0, sizeof(entry.router));
962 } else if (otype == DHCPV6_OPT_IA_ADDR) {
963 struct dhcpv6_ia_addr *addr = (void*)&odata[-4];
964 if (olen + 4U < sizeof(*addr))
967 entry.preferred = ntohl(addr->preferred);
968 entry.valid = ntohl(addr->valid);
970 if (entry.preferred > entry.valid)
974 entry.target = addr->addr;
976 #ifdef EXT_PREFIX_CLASS
977 uint16_t stype, slen;
979 // Find prefix class, if any
980 dhcpv6_for_each_option(&addr[1], odata + olen,
982 if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
983 entry.class = sdata[0] << 8 | sdata[1];
986 odhcp6c_update_entry(STATE_IA_NA, &entry);
988 if (entry.valid > 0 && timeout > entry.valid)
989 timeout = entry.valid;