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
45 #define DHCPV6_SOL_MAX_RT_MIN 60
46 #define DHCPV6_SOL_MAX_RT_MAX 86400
47 #define DHCPV6_INF_MAX_RT_MIN 60
48 #define DHCPV6_INF_MAX_RT_MAX 86400
50 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
51 const uint8_t transaction[3], enum dhcpv6_msg type,
52 const struct in6_addr *daddr);
54 static int dhcpv6_parse_ia(void *opt, void *end);
56 static int dhcpv6_calc_refresh_timers(void);
57 static void dhcpv6_handle_status_code(_unused const enum dhcpv6_msg orig,
58 const uint16_t code, const void *status_msg, const int len,
60 static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig,
61 const struct dhcpv6_ia_hdr *ia_hdr, const uint16_t code,
62 const void *status_msg, const int len,
63 bool handled_status_codes[_DHCPV6_Status_Max],
65 static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand *cand);
66 static void dhcpv6_clear_all_server_cand(void);
68 static reply_handler dhcpv6_handle_reply;
69 static reply_handler dhcpv6_handle_advert;
70 static reply_handler dhcpv6_handle_rebind_reply;
71 static reply_handler dhcpv6_handle_reconfigure;
72 static int dhcpv6_commit_advert(void);
76 // RFC 3315 - 5.5 Timeout and Delay values
77 static struct dhcpv6_retx dhcpv6_retx[_DHCPV6_MSG_MAX] = {
78 [DHCPV6_MSG_UNKNOWN] = {false, 1, 120, 0, "<POLL>",
79 dhcpv6_handle_reconfigure, NULL},
80 [DHCPV6_MSG_SOLICIT] = {true, 1, DHCPV6_SOL_MAX_RT, 0, "SOLICIT",
81 dhcpv6_handle_advert, dhcpv6_commit_advert},
82 [DHCPV6_MSG_REQUEST] = {true, 1, DHCPV6_REQ_MAX_RT, 10, "REQUEST",
83 dhcpv6_handle_reply, NULL},
84 [DHCPV6_MSG_RENEW] = {false, 10, DHCPV6_REN_MAX_RT, 0, "RENEW",
85 dhcpv6_handle_reply, NULL},
86 [DHCPV6_MSG_REBIND] = {false, 10, DHCPV6_REB_MAX_RT, 0, "REBIND",
87 dhcpv6_handle_rebind_reply, NULL},
88 [DHCPV6_MSG_RELEASE] = {false, 1, 0, 5, "RELEASE", NULL, NULL},
89 [DHCPV6_MSG_DECLINE] = {false, 1, 0, 5, "DECLINE", NULL, NULL},
90 [DHCPV6_MSG_INFO_REQ] = {true, 1, DHCPV6_INF_MAX_RT, 0, "INFOREQ",
91 dhcpv6_handle_reply, NULL},
97 static int ifindex = -1;
98 static int64_t t1 = 0, t2 = 0, t3 = 0;
101 static int request_prefix = -1;
102 static enum odhcp6c_ia_mode na_mode = IA_MODE_NONE, pd_mode = IA_MODE_NONE;
103 static bool accept_reconfig = false;
106 static uint8_t reconf_key[16];
109 static unsigned int client_options = 0;
112 int init_dhcpv6(const char *ifname, unsigned int options, int sol_timeout)
114 client_options = options;
115 dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = sol_timeout;
117 sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
123 strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
124 if (ioctl(sock, SIOCGIFINDEX, &ifr) < 0)
126 ifindex = ifr.ifr_ifindex;
128 // Create client DUID
129 size_t client_id_len;
130 odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
131 if (client_id_len == 0) {
132 uint8_t duid[14] = {0, DHCPV6_OPT_CLIENTID, 0, 10, 0,
133 DHCPV6_DUID_LLADDR, 0, 1};
135 if (ioctl(sock, SIOCGIFHWADDR, &ifr) >= 0)
136 memcpy(&duid[8], ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
138 uint8_t zero[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
139 struct ifreq ifs[100], *ifp, *ifend;
142 ifc.ifc_len = sizeof(ifs);
144 if (!memcmp(&duid[8], zero, ETHER_ADDR_LEN) &&
145 ioctl(sock, SIOCGIFCONF, &ifc) >= 0) {
146 // If our interface doesn't have an address...
147 ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq));
148 for (ifp = ifc.ifc_req; ifp < ifend &&
149 !memcmp(&duid[8], zero, ETHER_ADDR_LEN); ifp++) {
150 memcpy(ifr.ifr_name, ifp->ifr_name,
151 sizeof(ifr.ifr_name));
152 if (ioctl(sock, SIOCGIFHWADDR, &ifr) < 0)
155 memcpy(&duid[8], ifr.ifr_hwaddr.sa_data,
160 odhcp6c_add_state(STATE_CLIENT_ID, duid, sizeof(duid));
164 if (!(client_options & DHCPV6_STRICT_OPTIONS)) {
166 htons(DHCPV6_OPT_SIP_SERVER_D),
167 htons(DHCPV6_OPT_SIP_SERVER_A),
168 htons(DHCPV6_OPT_DNS_SERVERS),
169 htons(DHCPV6_OPT_DNS_DOMAIN),
170 htons(DHCPV6_OPT_SNTP_SERVERS),
171 htons(DHCPV6_OPT_NTP_SERVER),
172 htons(DHCPV6_OPT_AFTR_NAME),
173 htons(DHCPV6_OPT_PD_EXCLUDE),
174 htons(DHCPV6_OPT_SOL_MAX_RT),
175 htons(DHCPV6_OPT_INF_MAX_RT),
176 #ifdef EXT_PREFIX_CLASS
177 htons(DHCPV6_OPT_PREFIX_CLASS),
180 odhcp6c_add_state(STATE_ORO, oro, sizeof(oro));
183 // Configure IPv6-options
185 setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val));
186 setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
187 setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val, sizeof(val));
189 setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &val, sizeof(val));
190 setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
192 struct sockaddr_in6 client_addr = { .sin6_family = AF_INET6,
193 .sin6_port = htons(DHCPV6_CLIENT_PORT), .sin6_flowinfo = 0 };
194 if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr)) < 0)
201 void dhcpv6_set_ia_mode(enum odhcp6c_ia_mode na, enum odhcp6c_ia_mode pd)
207 static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
211 gethostname(fqdn_buf, sizeof(fqdn_buf));
218 size_t fqdn_len = 5 + dn_comp(fqdn_buf, fqdn.data,
219 sizeof(fqdn.data), NULL, NULL);
220 fqdn.type = htons(DHCPV6_OPT_FQDN);
221 fqdn.len = htons(fqdn_len - 4);
227 void *cl_id = odhcp6c_get_state(STATE_CLIENT_ID, &cl_id_len);
231 void *srv_id = odhcp6c_get_state(STATE_SERVER_ID, &srv_id_len);
234 size_t ia_pd_entries, ia_pd_len = 0;
237 if (type == DHCPV6_MSG_SOLICIT) {
238 odhcp6c_clear_state(STATE_IA_PD);
240 struct odhcp6c_request_prefix *request_prefixes = odhcp6c_get_state(STATE_IA_PD_INIT, &n_prefixes);
241 n_prefixes /= sizeof(struct odhcp6c_request_prefix);
243 ia_pd = alloca(n_prefixes * (sizeof(struct dhcpv6_ia_hdr) + sizeof(struct dhcpv6_ia_prefix)));
245 for (size_t i = 0; i < n_prefixes; i++) {
246 struct dhcpv6_ia_hdr hdr_ia_pd = {
247 htons(DHCPV6_OPT_IA_PD),
248 htons(sizeof(hdr_ia_pd) - 4 + sizeof(struct dhcpv6_ia_prefix)),
249 request_prefixes[i].iaid, 0, 0
251 struct dhcpv6_ia_prefix pref = {
252 .type = htons(DHCPV6_OPT_IA_PREFIX),
253 .len = htons(25), .prefix = request_prefixes[i].length
255 memcpy(ia_pd + ia_pd_len, &hdr_ia_pd, sizeof(hdr_ia_pd));
256 ia_pd_len += sizeof(hdr_ia_pd);
257 memcpy(ia_pd + ia_pd_len, &pref, sizeof(pref));
258 ia_pd_len += sizeof(pref);
261 struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
262 ia_pd_entries /= sizeof(*e);
264 // we're too lazy to count our distinct IAIDs,
265 // so just allocate maximally needed space
266 ia_pd = alloca(ia_pd_entries * (sizeof(struct dhcpv6_ia_prefix) + 10 +
267 sizeof(struct dhcpv6_ia_hdr)));
269 for (size_t i = 0; i < ia_pd_entries; ++i) {
270 uint32_t iaid = e[i].iaid;
272 // check if this is an unprocessed IAID and skip if not.
274 for (int j = i-1; j >= 0; j--) {
275 if (e[j].iaid == iaid) {
285 struct dhcpv6_ia_hdr hdr_ia_pd = {
286 htons(DHCPV6_OPT_IA_PD),
287 htons(sizeof(hdr_ia_pd) - 4),
291 memcpy(ia_pd + ia_pd_len, &hdr_ia_pd, sizeof(hdr_ia_pd));
292 struct dhcpv6_ia_hdr *hdr = (struct dhcpv6_ia_hdr *) (ia_pd + ia_pd_len);
293 ia_pd_len += sizeof(hdr_ia_pd);
295 for (size_t j = i; j < ia_pd_entries; j++) {
296 if (e[j].iaid != iaid)
300 if (e[j].priority > 0)
301 ex_len = ((e[j].priority - e[j].length - 1) / 8) + 6;
303 struct dhcpv6_ia_prefix p = {
304 .type = htons(DHCPV6_OPT_IA_PREFIX),
305 .len = htons(sizeof(p) - 4U + ex_len),
306 .prefix = e[j].length,
310 memcpy(ia_pd + ia_pd_len, &p, sizeof(p));
311 ia_pd_len += sizeof(p);
314 ia_pd[ia_pd_len++] = 0;
315 ia_pd[ia_pd_len++] = DHCPV6_OPT_PD_EXCLUDE;
316 ia_pd[ia_pd_len++] = 0;
317 ia_pd[ia_pd_len++] = ex_len - 4;
318 ia_pd[ia_pd_len++] = e[j].priority;
320 uint32_t excl = ntohl(e[j].router.s6_addr32[1]);
321 excl >>= (64 - e[j].priority);
322 excl <<= 8 - ((e[j].priority - e[j].length) % 8);
324 for (size_t i = ex_len - 5; i > 0; --i, excl >>= 8)
325 ia_pd[ia_pd_len + i] = excl & 0xff;
326 ia_pd_len += ex_len - 5;
329 hdr->len = htons(ntohs(hdr->len) + ntohs(p.len) + 4U);
334 if (ia_pd_entries > 0)
338 size_t ia_na_entries, ia_na_len = 0;
340 struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
341 ia_na_entries /= sizeof(*e);
343 struct dhcpv6_ia_hdr hdr_ia_na = {
344 htons(DHCPV6_OPT_IA_NA),
345 htons(sizeof(hdr_ia_na) - 4),
349 struct dhcpv6_ia_addr pa[ia_na_entries];
350 for (size_t i = 0; i < ia_na_entries; ++i) {
351 pa[i].type = htons(DHCPV6_OPT_IA_ADDR);
352 pa[i].len = htons(sizeof(pa[i]) - 4U);
353 pa[i].addr = e[i].target;
359 ia_na_len = sizeof(pa);
360 hdr_ia_na.len = htons(ntohs(hdr_ia_na.len) + ia_na_len);
362 // Reconfigure Accept
366 } reconf_accept = {htons(DHCPV6_OPT_RECONF_ACCEPT), 0};
368 // Request Information Refresh
369 uint16_t oro_refresh = htons(DHCPV6_OPT_INFO_REFRESH);
373 void *oro = odhcp6c_get_state(STATE_ORO, &oro_len);
377 uint16_t elapsed_type;
378 uint16_t elapsed_len;
379 uint16_t elapsed_value;
383 type, {trid[0], trid[1], trid[2]},
384 htons(DHCPV6_OPT_ELAPSED), htons(2),
385 htons((ecs > 0xffff) ? 0xffff : ecs),
386 htons(DHCPV6_OPT_ORO), htons(oro_len),
389 struct iovec iov[] = {
394 {srv_id, srv_id_len},
395 {&reconf_accept, sizeof(reconf_accept)},
397 {&hdr_ia_na, sizeof(hdr_ia_na)},
402 size_t cnt = ARRAY_SIZE(iov);
403 if (type == DHCPV6_MSG_INFO_REQ) {
405 iov[2].iov_len = sizeof(oro_refresh);
406 hdr.oro_len = htons(oro_len + sizeof(oro_refresh));
407 } else if (!request_prefix) {
411 // Disable IAs if not used
412 if (type != DHCPV6_MSG_SOLICIT) {
418 if (na_mode == IA_MODE_NONE)
421 if (!(client_options & DHCPV6_ACCEPT_RECONFIGURE))
424 if (!(client_options & DHCPV6_CLIENT_FQDN))
427 struct sockaddr_in6 srv = {AF_INET6, htons(DHCPV6_SERVER_PORT),
428 0, ALL_DHCPV6_RELAYS, ifindex};
429 struct msghdr msg = {&srv, sizeof(srv), iov, cnt, NULL, 0, 0};
431 sendmsg(sock, &msg, 0);
435 static int64_t dhcpv6_rand_delay(int64_t time)
438 odhcp6c_random(&random, sizeof(random));
439 return (time * ((int64_t)random % 1000LL)) / 10000LL;
443 int dhcpv6_request(enum dhcpv6_msg type)
446 uint64_t timeout = UINT32_MAX;
447 struct dhcpv6_retx *retx = &dhcpv6_retx[type];
450 struct timespec ts = {0, 0};
451 ts.tv_nsec = dhcpv6_rand_delay(10 * DHCPV6_REQ_DELAY);
452 nanosleep(&ts, NULL);
455 if (type == DHCPV6_MSG_UNKNOWN)
457 else if (type == DHCPV6_MSG_RENEW)
458 timeout = (t2 > t1) ? t2 - t1 : 0;
459 else if (type == DHCPV6_MSG_REBIND)
460 timeout = (t3 > t2) ? t3 - t2 : 0;
465 syslog(LOG_NOTICE, "Starting %s transaction (timeout %llus, max rc %d)",
466 retx->name, (unsigned long long)timeout, retx->max_rc);
468 uint64_t start = odhcp6c_get_milli_time(), round_start = start, elapsed;
470 // Generate transaction ID
471 uint8_t trid[3] = {0, 0, 0};
472 if (type != DHCPV6_MSG_UNKNOWN)
473 odhcp6c_random(trid, sizeof(trid));
479 int64_t delay = dhcpv6_rand_delay(retx->init_timeo * 1000);
481 // First RT MUST be strictly greater than IRT for solicit messages (RFC3313 17.1.2)
482 while (type == DHCPV6_MSG_SOLICIT && delay <= 0)
483 delay = dhcpv6_rand_delay(retx->init_timeo * 1000);
485 rto = (retx->init_timeo * 1000 + delay);
488 rto = (2 * rto + dhcpv6_rand_delay(rto));
490 if (retx->max_timeo && (rto >= retx->max_timeo * 1000))
491 rto = retx->max_timeo * 1000 +
492 dhcpv6_rand_delay(retx->max_timeo * 1000);
494 // Calculate end for this round and elapsed time
495 uint64_t round_end = round_start + rto;
496 elapsed = round_start - start;
498 // Don't wait too long
499 if (round_end - start > timeout * 1000)
500 round_end = timeout * 1000 + start;
502 // Built and send package
503 if (type != DHCPV6_MSG_UNKNOWN) {
504 if (type != DHCPV6_MSG_SOLICIT)
505 syslog(LOG_NOTICE, "Send %s message (elapsed %llums, rc %d)",
506 retx->name, (unsigned long long)elapsed, rc);
507 dhcpv6_send(type, trid, elapsed / 10);
512 for (; len < 0 && (round_start < round_end);
513 round_start = odhcp6c_get_milli_time()) {
514 uint8_t buf[1536], cmsg_buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
515 struct iovec iov = {buf, sizeof(buf)};
516 struct msghdr msg = {NULL, 0, &iov, 1,
517 cmsg_buf, sizeof(cmsg_buf), 0};
518 struct in6_pktinfo *pktinfo = NULL;
520 // Check for pending signal
521 if (odhcp6c_signal_process())
524 // Set timeout for receiving
525 uint64_t t = round_end - round_start;
526 struct timeval timeout = {t / 1000, (t % 1000) * 1000};
527 setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO,
528 &timeout, sizeof(timeout));
531 len = recvmsg(sock, &msg, 0);
535 for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL;
536 ch = CMSG_NXTHDR(&msg, ch)) {
537 if (ch->cmsg_level == SOL_IPV6 &&
538 ch->cmsg_type == IPV6_PKTINFO) {
539 pktinfo = (struct in6_pktinfo *)CMSG_DATA(ch);
544 if (pktinfo == NULL) {
549 if (!dhcpv6_response_is_valid(buf, len, trid,
550 type, &pktinfo->ipi6_addr)) {
555 uint8_t *opt = &buf[4];
556 uint8_t *opt_end = opt + len - 4;
558 round_start = odhcp6c_get_milli_time();
559 elapsed = round_start - start;
560 syslog(LOG_NOTICE, "Got a valid reply after "
561 "%llums", (unsigned long long)elapsed);
563 if (retx->handler_reply)
564 len = retx->handler_reply(type, rc, opt, opt_end);
566 if (len > 0 && round_end - round_start > 1000)
567 round_end = 1000 + round_start;
571 if (retx->handler_finish)
572 len = retx->handler_finish();
573 } while (len < 0 && ((elapsed / 1000 < timeout) && (!retx->max_rc || rc < retx->max_rc)));
578 // Message validation checks according to RFC3315 chapter 15
579 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
580 const uint8_t transaction[3], enum dhcpv6_msg type,
581 const struct in6_addr *daddr)
583 const struct dhcpv6_header *rep = buf;
584 if (len < (ssize_t)sizeof(*rep) || memcmp(rep->tr_id,
585 transaction, sizeof(rep->tr_id)))
586 return false; // Invalid reply
588 if (type == DHCPV6_MSG_SOLICIT) {
589 if (rep->msg_type != DHCPV6_MSG_ADVERT &&
590 rep->msg_type != DHCPV6_MSG_REPLY)
592 } else if (type == DHCPV6_MSG_UNKNOWN) {
593 if (!accept_reconfig || rep->msg_type != DHCPV6_MSG_RECONF)
595 } else if (rep->msg_type != DHCPV6_MSG_REPLY) {
599 uint8_t *end = ((uint8_t*)buf) + len, *odata = NULL,
600 rcmsg = DHCPV6_MSG_UNKNOWN;
601 uint16_t otype, olen = UINT16_MAX;
602 bool clientid_ok = false, serverid_ok = false, rcauth_ok = false,
603 ia_present = false, options_valid = true;
605 size_t client_id_len, server_id_len;
606 void *client_id = odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
607 void *server_id = odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
609 dhcpv6_for_each_option(&rep[1], end, otype, olen, odata) {
610 if (otype == DHCPV6_OPT_CLIENTID) {
611 clientid_ok = (olen + 4U == client_id_len) && !memcmp(
612 &odata[-4], client_id, client_id_len);
613 } else if (otype == DHCPV6_OPT_SERVERID) {
615 serverid_ok = (olen + 4U == server_id_len) && !memcmp(
616 &odata[-4], server_id, server_id_len);
619 } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
620 sizeof(struct dhcpv6_auth_reconfigure)) {
621 struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
622 if (r->protocol != 3 || r->algorithm != 1 || r->reconf_type != 2)
626 uint8_t serverhash[16], secretbytes[16], hash[16];
627 memcpy(serverhash, r->key, sizeof(serverhash));
628 memset(r->key, 0, sizeof(r->key));
629 memcpy(secretbytes, reconf_key, sizeof(secretbytes));
631 for (size_t i = 0; i < sizeof(secretbytes); ++i)
632 secretbytes[i] ^= 0x36;
635 md5_hash(secretbytes, sizeof(secretbytes), &md5);
636 md5_hash(buf, len, &md5);
639 for (size_t i = 0; i < sizeof(secretbytes); ++i) {
640 secretbytes[i] ^= 0x36;
641 secretbytes[i] ^= 0x5c;
645 md5_hash(secretbytes, sizeof(secretbytes), &md5);
646 md5_hash(hash, 16, &md5);
649 rcauth_ok = !memcmp(hash, serverhash, sizeof(hash));
650 } else if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1) {
652 } else if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)) {
654 if (olen < sizeof(struct dhcpv6_ia_hdr))
655 options_valid = false;
657 else if ((otype == DHCPV6_OPT_IA_ADDR) || (otype == DHCPV6_OPT_IA_PREFIX) ||
658 (otype == DHCPV6_OPT_PD_EXCLUDE)) {
659 // Options are not allowed on global level
660 options_valid = false;
664 if (!options_valid || ((odata + olen) > end))
667 if (type == DHCPV6_MSG_INFO_REQ && ia_present)
670 if (rep->msg_type == DHCPV6_MSG_RECONF) {
671 if ((rcmsg != DHCPV6_MSG_RENEW && rcmsg != DHCPV6_MSG_INFO_REQ) ||
672 (rcmsg == DHCPV6_MSG_INFO_REQ && ia_present) ||
673 !rcauth_ok || IN6_IS_ADDR_MULTICAST(daddr))
677 return clientid_ok && serverid_ok;
681 int dhcpv6_poll_reconfigure(void)
683 int ret = dhcpv6_request(DHCPV6_MSG_UNKNOWN);
685 ret = dhcpv6_request(ret);
691 static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig, const int rc,
692 const void *opt, const void *end)
694 uint16_t otype, olen;
695 uint8_t *odata, msg = DHCPV6_MSG_RENEW;
696 dhcpv6_for_each_option(opt, end, otype, olen, odata)
697 if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1 && (
698 odata[0] == DHCPV6_MSG_RENEW ||
699 odata[0] == DHCPV6_MSG_INFO_REQ))
702 dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, rc, NULL, NULL);
707 // Collect all advertised servers
708 static int dhcpv6_handle_advert(enum dhcpv6_msg orig, const int rc,
709 const void *opt, const void *end)
711 uint16_t olen, otype;
712 uint8_t *odata, pref = 0;
713 struct dhcpv6_server_cand cand = {false, false, 0, 0, {0},
715 DHCPV6_INF_MAX_RT, NULL, NULL, 0, 0};
716 bool have_na = false;
719 dhcpv6_for_each_option(opt, end, otype, olen, odata) {
720 if (orig == DHCPV6_MSG_SOLICIT &&
721 (otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA) &&
722 olen > sizeof(struct dhcpv6_ia_hdr)) {
723 struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
724 dhcpv6_parse_ia(ia_hdr, odata + olen + sizeof(*ia_hdr));
727 if (otype == DHCPV6_OPT_SERVERID && olen <= 130) {
728 memcpy(cand.duid, odata, olen);
729 cand.duid_len = olen;
730 } else if (otype == DHCPV6_OPT_STATUS && olen >= 2) {
731 int error = ((int)odata[0] << 8 | (int)odata[1]);
734 case DHCPV6_NoPrefixAvail:
735 // Status code on global level
736 cand.preference -= 2000;
742 } else if (otype == DHCPV6_OPT_PREF && olen >= 1 &&
743 cand.preference >= 0) {
744 cand.preference = pref = odata[0];
745 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
746 cand.wants_reconfigure = true;
747 } else if (otype == DHCPV6_OPT_SOL_MAX_RT && olen == 4) {
748 uint32_t sol_max_rt = ntohl(*((uint32_t *)odata));
749 if (sol_max_rt >= DHCPV6_SOL_MAX_RT_MIN &&
750 sol_max_rt <= DHCPV6_SOL_MAX_RT_MAX)
751 cand.sol_max_rt = sol_max_rt;
752 } else if (otype == DHCPV6_OPT_INF_MAX_RT && olen == 4) {
753 uint32_t inf_max_rt = ntohl(*((uint32_t *)odata));
754 if (inf_max_rt >= DHCPV6_INF_MAX_RT_MIN &&
755 inf_max_rt <= DHCPV6_INF_MAX_RT_MAX)
756 cand.inf_max_rt = inf_max_rt;
757 } else if (otype == DHCPV6_OPT_IA_PD && request_prefix) {
758 struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
759 uint8_t *oend = odata + olen, *d;
760 dhcpv6_for_each_option(&h[1], oend, otype, olen, d) {
761 if (otype == DHCPV6_OPT_IA_PREFIX && (olen + 4) >=
762 (uint16_t)sizeof(struct dhcpv6_ia_prefix)) {
763 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&d[-4];
767 } else if (otype == DHCPV6_OPT_IA_NA) {
768 struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
769 uint8_t *oend = odata + olen, *d;
770 dhcpv6_for_each_option(&h[1], oend, otype, olen, d)
771 if (otype == DHCPV6_OPT_IA_ADDR)
776 if ((!have_na && na_mode == IA_MODE_FORCE) ||
777 (!have_pd && pd_mode == IA_MODE_FORCE)) {
779 * RFC7083 states to process the SOL_MAX_RT and
780 * INF_MAX_RT options even if the DHCPv6 server
781 * did not propose any IA_NA and/or IA_PD
783 dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = cand.sol_max_rt;
784 dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = cand.inf_max_rt;
788 if (na_mode != IA_MODE_NONE && !have_na) {
789 cand.has_noaddravail = true;
790 cand.preference -= 1000;
793 if (pd_mode != IA_MODE_NONE) {
795 cand.preference += 2000 + (128 - have_pd);
797 cand.preference -= 2000;
800 if (cand.duid_len > 0) {
801 cand.ia_na = odhcp6c_move_state(STATE_IA_NA, &cand.ia_na_len);
802 cand.ia_pd = odhcp6c_move_state(STATE_IA_PD, &cand.ia_pd_len);
803 dhcpv6_add_server_cand(&cand);
806 return (rc > 1 || (pref == 255 && cand.preference > 0)) ? 1 : -1;
810 static int dhcpv6_commit_advert(void)
812 return dhcpv6_promote_server_cand();
816 static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig, const int rc,
817 const void *opt, const void *end)
819 dhcpv6_handle_advert(orig, rc, opt, end);
820 if (dhcpv6_commit_advert() < 0)
823 return dhcpv6_handle_reply(orig, rc, opt, end);
827 static int dhcpv6_handle_reply(enum dhcpv6_msg orig, _unused const int rc,
828 const void *opt, const void *end)
831 uint16_t otype, olen;
832 uint32_t refresh = UINT32_MAX;
834 bool handled_status_codes[_DHCPV6_Status_Max] = { false, };
838 if (orig == DHCPV6_MSG_UNKNOWN) {
839 static time_t last_update = 0;
840 time_t now = odhcp6c_get_milli_time() / 1000;
842 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
859 if (orig == DHCPV6_MSG_REQUEST && !odhcp6c_is_bound()) {
860 // Delete NA and PD we have in the state from the Advert
861 odhcp6c_clear_state(STATE_IA_NA);
862 odhcp6c_clear_state(STATE_IA_PD);
866 odhcp6c_clear_state(STATE_DNS);
867 odhcp6c_clear_state(STATE_SEARCH);
868 odhcp6c_clear_state(STATE_SNTP_IP);
869 odhcp6c_clear_state(STATE_NTP_IP);
870 odhcp6c_clear_state(STATE_NTP_FQDN);
871 odhcp6c_clear_state(STATE_SIP_IP);
872 odhcp6c_clear_state(STATE_SIP_FQDN);
873 odhcp6c_clear_state(STATE_AFTR_NAME);
876 // Parse and find all matching IAs
877 dhcpv6_for_each_option(opt, end, otype, olen, odata) {
878 if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)
879 && olen > sizeof(struct dhcpv6_ia_hdr)) {
880 struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
883 if (ia_hdr->iaid != 1 && otype == DHCPV6_OPT_IA_NA)
886 uint16_t code = DHCPV6_Success;
887 uint16_t stype, slen;
889 // Get and handle status code
890 dhcpv6_for_each_option(&ia_hdr[1], odata + olen,
891 stype, slen, sdata) {
892 if (stype == DHCPV6_OPT_STATUS && slen >= 2) {
893 uint8_t *mdata = (slen > 2) ? &sdata[2] : NULL;
894 uint16_t mlen = (slen > 2) ? slen - 2 : 0;
896 code = ((int)sdata[0]) << 8 | ((int)sdata[1]);
898 if (code == DHCPV6_Success)
901 dhcpv6_handle_ia_status_code(orig, ia_hdr,
902 code, mdata, mlen, handled_status_codes, &ret);
911 if (code != DHCPV6_Success)
914 dhcpv6_parse_ia(ia_hdr, odata + olen + sizeof(*ia_hdr));
915 } else if (otype == DHCPV6_OPT_STATUS && olen >= 2) {
916 uint8_t *mdata = (olen > 2) ? &odata[2] : NULL;
917 uint16_t mlen = (olen > 2) ? olen - 2 : 0;
918 uint16_t code = ((int)odata[0]) << 8 | ((int)odata[1]);
920 dhcpv6_handle_status_code(orig, code, mdata, mlen, &ret);
922 else if (otype == DHCPV6_OPT_DNS_SERVERS) {
924 odhcp6c_add_state(STATE_DNS, odata, olen);
925 } else if (otype == DHCPV6_OPT_DNS_DOMAIN) {
926 odhcp6c_add_state(STATE_SEARCH, odata, olen);
927 } else if (otype == DHCPV6_OPT_SNTP_SERVERS) {
929 odhcp6c_add_state(STATE_SNTP_IP, odata, olen);
930 } else if (otype == DHCPV6_OPT_NTP_SERVER) {
931 uint16_t stype, slen;
933 // Test status and bail if error
934 dhcpv6_for_each_option(odata, odata + olen,
935 stype, slen, sdata) {
936 if (slen == 16 && (stype == NTP_MC_ADDR ||
937 stype == NTP_SRV_ADDR))
938 odhcp6c_add_state(STATE_NTP_IP,
940 else if (slen > 0 && stype == NTP_SRV_FQDN)
941 odhcp6c_add_state(STATE_NTP_FQDN,
944 } else if (otype == DHCPV6_OPT_SIP_SERVER_A) {
946 odhcp6c_add_state(STATE_SIP_IP, odata, olen);
947 } else if (otype == DHCPV6_OPT_SIP_SERVER_D) {
948 odhcp6c_add_state(STATE_SIP_FQDN, odata, olen);
949 } else if (otype == DHCPV6_OPT_INFO_REFRESH && olen >= 4) {
950 refresh = ntohl(*((uint32_t*)odata));
951 } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
952 sizeof(struct dhcpv6_auth_reconfigure)) {
953 struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
954 if (r->protocol == 3 && r->algorithm == 1 &&
956 memcpy(reconf_key, r->key, sizeof(r->key));
957 } else if (otype == DHCPV6_OPT_AFTR_NAME && olen > 3) {
959 odhcp6c_get_state(STATE_AFTR_NAME, &cur_len);
961 odhcp6c_add_state(STATE_AFTR_NAME, odata, olen);
962 } else if (otype == DHCPV6_OPT_SOL_MAX_RT && olen == 4) {
963 uint32_t sol_max_rt = ntohl(*((uint32_t *)odata));
964 if (sol_max_rt >= DHCPV6_SOL_MAX_RT_MIN &&
965 sol_max_rt <= DHCPV6_SOL_MAX_RT_MAX)
966 dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = sol_max_rt;
967 } else if (otype == DHCPV6_OPT_INF_MAX_RT && olen == 4) {
968 uint32_t inf_max_rt = ntohl(*((uint32_t *)odata));
969 if (inf_max_rt >= DHCPV6_INF_MAX_RT_MIN &&
970 inf_max_rt <= DHCPV6_INF_MAX_RT_MAX)
971 dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = inf_max_rt;
972 }else if (otype != DHCPV6_OPT_CLIENTID &&
973 otype != DHCPV6_OPT_SERVERID) {
974 odhcp6c_add_state(STATE_CUSTOM_OPTS,
975 &odata[-4], olen + 4);
979 if (orig != DHCPV6_MSG_INFO_REQ) {
980 // Update refresh timers if no fatal status code was received
981 if ((ret > 0) && dhcpv6_calc_refresh_timers()) {
983 case DHCPV6_MSG_RENEW:
984 // Send further renews if T1 is not set
988 case DHCPV6_MSG_REBIND:
989 // Send further rebinds if T1 and T2 is not set
994 case DHCPV6_MSG_REQUEST:
995 // All server candidates can be cleared if not yet bound
996 if (!odhcp6c_is_bound())
997 dhcpv6_clear_all_server_cand();
1005 // All server candidates can be cleared if not yet bound
1006 if (!odhcp6c_is_bound())
1007 dhcpv6_clear_all_server_cand();
1016 static int dhcpv6_parse_ia(void *opt, void *end)
1018 struct dhcpv6_ia_hdr *ia_hdr = (struct dhcpv6_ia_hdr *)opt;
1021 uint16_t otype, olen;
1024 t1 = ntohl(ia_hdr->t1);
1025 t2 = ntohl(ia_hdr->t2);
1030 // Update address IA
1031 dhcpv6_for_each_option(&ia_hdr[1], end, otype, olen, odata) {
1032 struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0,
1033 IN6ADDR_ANY_INIT, 0, 0, 0, 0, 0, 0};
1035 entry.iaid = ia_hdr->iaid;
1037 if (otype == DHCPV6_OPT_IA_PREFIX) {
1038 struct dhcpv6_ia_prefix *prefix = (void*)&odata[-4];
1039 if (olen + 4U < sizeof(*prefix))
1042 entry.valid = ntohl(prefix->valid);
1043 entry.preferred = ntohl(prefix->preferred);
1045 if (entry.preferred > entry.valid)
1048 entry.t1 = (t1 ? t1 : (entry.preferred != UINT32_MAX ? 0.5 * entry.preferred : UINT32_MAX));
1049 entry.t2 = (t2 ? t2 : (entry.preferred != UINT32_MAX ? 0.8 * entry.preferred : UINT32_MAX));
1050 if (entry.t1 > entry.t2)
1051 entry.t1 = entry.t2;
1053 entry.length = prefix->prefix;
1054 entry.target = prefix->addr;
1055 uint16_t stype, slen;
1058 #ifdef EXT_PREFIX_CLASS
1059 // Find prefix class, if any
1060 dhcpv6_for_each_option(&prefix[1], odata + olen,
1062 if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
1063 entry.class = sdata[0] << 8 | sdata[1];
1068 dhcpv6_for_each_option(odata + sizeof(*prefix) - 4U,
1069 odata + olen, stype, slen, sdata) {
1070 if (stype != DHCPV6_OPT_PD_EXCLUDE || slen < 2)
1073 uint8_t elen = sdata[0];
1077 if (elen <= 32 || elen <= entry.length) {
1083 uint8_t bytes = ((elen - entry.length - 1) / 8) + 1;
1084 if (slen <= bytes) {
1089 uint32_t exclude = 0;
1091 exclude = exclude << 8 | sdata[bytes];
1094 exclude >>= 8 - ((elen - entry.length) % 8);
1095 exclude <<= 64 - elen;
1097 // Abusing router & priority fields for exclusion
1098 entry.router = entry.target;
1099 entry.router.s6_addr32[1] |= htonl(exclude);
1100 entry.priority = elen;
1104 odhcp6c_update_entry(STATE_IA_PD, &entry);
1109 memset(&entry.router, 0, sizeof(entry.router));
1110 } else if (otype == DHCPV6_OPT_IA_ADDR) {
1111 struct dhcpv6_ia_addr *addr = (void*)&odata[-4];
1112 if (olen + 4U < sizeof(*addr))
1115 entry.preferred = ntohl(addr->preferred);
1116 entry.valid = ntohl(addr->valid);
1118 if (entry.preferred > entry.valid)
1121 entry.t1 = (t1 ? t1 : (entry.preferred != UINT32_MAX ? 0.5 * entry.preferred : UINT32_MAX));
1122 entry.t2 = (t2 ? t2 : (entry.preferred != UINT32_MAX ? 0.8 * entry.preferred : UINT32_MAX));
1123 if (entry.t1 > entry.t2)
1124 entry.t1 = entry.t2;
1127 entry.target = addr->addr;
1129 #ifdef EXT_PREFIX_CLASS
1130 uint16_t stype, slen;
1132 // Find prefix class, if any
1133 dhcpv6_for_each_option(&addr[1], odata + olen,
1135 if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
1136 entry.class = sdata[0] << 8 | sdata[1];
1139 odhcp6c_update_entry(STATE_IA_NA, &entry);
1147 static int dhcpv6_calc_refresh_timers(void)
1149 struct odhcp6c_entry *e;
1150 size_t ia_na_entries, ia_pd_entries, i;
1151 int64_t l_t1 = UINT32_MAX, l_t2 = UINT32_MAX, l_t3 = 0;
1153 e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
1154 ia_na_entries /= sizeof(*e);
1155 for (i = 0; i < ia_na_entries; i++) {
1162 if (e[i].valid > l_t3)
1166 e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
1167 ia_pd_entries /= sizeof(*e);
1168 for (i = 0; i < ia_pd_entries; i++) {
1175 if (e[i].valid > l_t3)
1179 if (ia_pd_entries || ia_na_entries) {
1187 return (int)(ia_pd_entries + ia_na_entries);
1191 static void dhcpv6_log_status_code(const uint16_t code, const char *scope,
1192 const void *status_msg, const int len)
1194 uint8_t buf[len + 3];
1196 memset(buf, 0, sizeof(buf));
1199 memcpy(&buf[1], status_msg, len);
1203 syslog(LOG_WARNING, "Server returned %s status %i %s",
1208 static void dhcpv6_handle_status_code(const enum dhcpv6_msg orig,
1209 const uint16_t code, const void *status_msg, const int len,
1212 dhcpv6_log_status_code(code, "message", status_msg, len);
1215 case DHCPV6_UnspecFail:
1220 case DHCPV6_UseMulticast:
1221 // TODO handle multicast status code
1224 case DHCPV6_NoAddrsAvail:
1225 case DHCPV6_NoPrefixAvail:
1226 if (orig == DHCPV6_MSG_REQUEST)
1227 *ret = 0; // Failure
1236 static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig,
1237 const struct dhcpv6_ia_hdr *ia_hdr, const uint16_t code,
1238 const void *status_msg, const int len,
1239 bool handled_status_codes[_DHCPV6_Status_Max], int *ret)
1241 dhcpv6_log_status_code(code, ia_hdr->type == DHCPV6_OPT_IA_NA ?
1242 "IA_NA" : "IA_PD", status_msg, len);
1245 case DHCPV6_NoBinding:
1247 case DHCPV6_MSG_RENEW:
1248 case DHCPV6_MSG_REBIND:
1249 if ((*ret > 0) && !handled_status_codes[code])
1250 *ret = dhcpv6_request(DHCPV6_MSG_REQUEST);
1258 case DHCPV6_NoAddrsAvail:
1259 case DHCPV6_NoPrefixAvail:
1261 case DHCPV6_MSG_REQUEST:
1270 case DHCPV6_NotOnLink:
1271 // TODO handle not onlink in case of confirm
1279 static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand *cand)
1282 struct dhcpv6_server_cand *c = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
1284 // Remove identical duid server candidate
1285 for (i = 0; i < cand_len / sizeof(*c); ++i) {
1286 if (cand->duid_len == c[i].duid_len &&
1287 !memcmp(cand->duid, c[i].duid, cand->duid_len)) {
1290 odhcp6c_remove_state(STATE_SERVER_CAND, i * sizeof(*c), sizeof(*c));
1295 for (i = 0, c = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
1296 i < cand_len / sizeof(*c); ++i) {
1297 if (c[i].preference < cand->preference)
1301 odhcp6c_insert_state(STATE_SERVER_CAND, i * sizeof(*c), cand, sizeof(*cand));
1304 static void dhcpv6_clear_all_server_cand(void)
1307 struct dhcpv6_server_cand *c = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
1309 // Server candidates need deep delete for IA_NA/IA_PD
1310 for (i = 0; i < cand_len / sizeof(*c); ++i) {
1314 odhcp6c_clear_state(STATE_SERVER_CAND);
1317 int dhcpv6_promote_server_cand(void)
1320 struct dhcpv6_server_cand *cand = odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
1322 int ret = (na_mode == IA_MODE_NONE && pd_mode == IA_MODE_NONE) ?
1323 DHCPV6_STATELESS : DHCPV6_STATEFUL;
1325 // Clear lingering candidate state info
1326 odhcp6c_clear_state(STATE_SERVER_ID);
1327 odhcp6c_clear_state(STATE_IA_NA);
1328 odhcp6c_clear_state(STATE_IA_PD);
1333 if (cand->has_noaddravail && na_mode == IA_MODE_TRY) {
1334 na_mode = IA_MODE_NONE;
1336 dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = cand->sol_max_rt;
1337 dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = cand->inf_max_rt;
1339 return dhcpv6_request(DHCPV6_MSG_SOLICIT);
1342 hdr[0] = htons(DHCPV6_OPT_SERVERID);
1343 hdr[1] = htons(cand->duid_len);
1344 odhcp6c_add_state(STATE_SERVER_ID, hdr, sizeof(hdr));
1345 odhcp6c_add_state(STATE_SERVER_ID, cand->duid, cand->duid_len);
1346 accept_reconfig = cand->wants_reconfigure;
1347 if (cand->ia_na_len) {
1348 odhcp6c_add_state(STATE_IA_NA, cand->ia_na, cand->ia_na_len);
1350 if (na_mode != IA_MODE_NONE)
1351 ret = DHCPV6_STATEFUL;
1353 if (cand->ia_pd_len) {
1354 odhcp6c_add_state(STATE_IA_PD, cand->ia_pd, cand->ia_pd_len);
1357 ret = DHCPV6_STATEFUL;
1360 dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = cand->sol_max_rt;
1361 dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = cand->inf_max_rt;
1363 odhcp6c_remove_state(STATE_SERVER_CAND, 0, sizeof(*cand));