2 * Copyright (C) 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.
18 #include "libubox/md5.h"
19 #include "libubox/usock.h"
33 #include <arpa/inet.h>
34 #include <sys/timerfd.h>
37 static void update(struct interface *iface);
38 static void reconf_timer(struct uloop_timeout *event);
39 static struct uloop_timeout reconf_event = {.cb = reconf_timer};
40 static uint32_t serial = 0;
41 static uint8_t statemd5[16];
44 int dhcpv6_ia_init(void)
46 uloop_timeout_set(&reconf_event, 2000);
51 void free_dhcpv6_assignment(struct dhcpv6_assignment *c)
53 if (c->managed_sock.fd.registered) {
54 ustream_free(&c->managed_sock.stream);
55 close(c->managed_sock.fd.fd);
68 int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
70 if (!enable && iface->ia_assignments.next) {
71 struct dhcpv6_assignment *c;
72 while (!list_empty(&iface->ia_assignments)) {
73 c = list_first_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
74 free_dhcpv6_assignment(c);
78 if (iface->dhcpv6 == RELAYD_SERVER) {
79 if (!iface->ia_assignments.next)
80 INIT_LIST_HEAD(&iface->ia_assignments);
82 if (list_empty(&iface->ia_assignments)) {
83 struct dhcpv6_assignment *border = calloc(1, sizeof(*border));
85 syslog(LOG_ERR, "Calloc failed for border on interface %s", iface->ifname);
90 list_add(&border->head, &iface->ia_assignments);
95 // Parse static entries
97 list_for_each_entry(lease, &leases, head) {
99 struct dhcpv6_assignment *a = calloc(1, sizeof(*a) + lease->duid_len);
101 syslog(LOG_ERR, "Calloc failed for static lease assignment on interface %s",
106 a->clid_len = lease->duid_len;
109 a->assigned = lease->hostid;
111 uint32_t i4a = ntohl(lease->ipaddr.s_addr) & 0xff;
112 a->assigned = ((i4a / 100) << 8) | (((i4a % 100) / 10) << 4) | (i4a % 10);
114 odhcpd_urandom(a->key, sizeof(a->key));
115 memcpy(a->clid_data, lease->duid, a->clid_len);
116 memcpy(a->mac, lease->mac.ether_addr_octet, sizeof(a->mac));
118 // Assign to all interfaces
119 struct dhcpv6_assignment *c;
120 list_for_each_entry(c, &iface->ia_assignments, head) {
121 if (c->length != 128 || c->assigned > a->assigned) {
122 list_add_tail(&a->head, &c->head);
124 } else if (c->assigned == a->assigned) {
125 // Already an assignment with that number
131 if (lease->hostname[0]) {
133 a->hostname = strdup(lease->hostname);
146 static int send_reconf(struct interface *iface, struct dhcpv6_assignment *assign)
149 struct dhcpv6_client_header hdr;
153 uint16_t hardware_type;
158 struct dhcpv6_auth_reconfigure auth;
161 uint8_t clid_data[128];
162 } __attribute__((packed)) reconf_msg = {
163 .hdr = {DHCPV6_MSG_RECONFIGURE, {0, 0, 0}},
164 .srvid_type = htons(DHCPV6_OPT_SERVERID),
165 .srvid_len = htons(10),
166 .duid_type = htons(3),
167 .hardware_type = htons(1),
168 .msg_type = htons(DHCPV6_OPT_RECONF_MSG),
170 .msg_id = DHCPV6_MSG_RENEW,
171 .auth = {htons(DHCPV6_OPT_AUTH),
172 htons(sizeof(reconf_msg.auth) - 4), 3, 1, 0,
173 {htonl(time(NULL)), htonl(++serial)}, 2, {0}},
174 .clid_type = htons(DHCPV6_OPT_CLIENTID),
175 .clid_len = htons(assign->clid_len),
179 odhcpd_get_mac(iface, reconf_msg.mac);
180 memcpy(reconf_msg.clid_data, assign->clid_data, assign->clid_len);
181 struct iovec iov = {&reconf_msg, sizeof(reconf_msg) - 128 + assign->clid_len};
184 uint8_t secretbytes[64];
185 memset(secretbytes, 0, sizeof(secretbytes));
186 memcpy(secretbytes, assign->key, sizeof(assign->key));
188 for (size_t i = 0; i < sizeof(secretbytes); ++i)
189 secretbytes[i] ^= 0x36;
192 md5_hash(secretbytes, sizeof(secretbytes), &md5);
193 md5_hash(iov.iov_base, iov.iov_len, &md5);
194 md5_end(reconf_msg.auth.key, &md5);
196 for (size_t i = 0; i < sizeof(secretbytes); ++i) {
197 secretbytes[i] ^= 0x36;
198 secretbytes[i] ^= 0x5c;
202 md5_hash(secretbytes, sizeof(secretbytes), &md5);
203 md5_hash(reconf_msg.auth.key, 16, &md5);
204 md5_end(reconf_msg.auth.key, &md5);
206 return odhcpd_send(iface->dhcpv6_event.uloop.fd, &assign->peer, &iov, 1, iface);
210 void dhcpv6_write_statefile(void)
215 if (config.dhcp_statefile) {
216 time_t now = odhcpd_time(), wall_time = time(NULL);
217 int fd = open(config.dhcp_statefile, O_CREAT | O_WRONLY | O_CLOEXEC, 0644);
221 lockf(fd, F_LOCK, 0);
224 FILE *fp = fdopen(fd, "w");
230 struct interface *iface;
231 list_for_each_entry(iface, &interfaces, head) {
232 if (iface->dhcpv6 != RELAYD_SERVER && iface->dhcpv4 != RELAYD_SERVER)
235 if (iface->dhcpv6 == RELAYD_SERVER && iface->ia_assignments.next) {
236 struct dhcpv6_assignment *c;
237 list_for_each_entry(c, &iface->ia_assignments, head) {
238 if (c->clid_len == 0 || c->managed_size < 0)
241 char ipbuf[INET6_ADDRSTRLEN];
244 odhcpd_hexlify(duidbuf, c->clid_data, c->clid_len);
246 // iface DUID iaid hostname lifetime assigned length [addrs...]
247 int l = snprintf(leasebuf, sizeof(leasebuf), "# %s %s %x %s %u %x %u ",
248 iface->ifname, duidbuf, ntohl(c->iaid),
249 (c->hostname ? c->hostname : "-"),
250 (unsigned)(c->valid_until > now ?
251 (c->valid_until - now + wall_time) : 0),
252 c->assigned, (unsigned)c->length);
254 struct in6_addr addr;
255 struct odhcpd_ipaddr *addrs = (c->managed) ? c->managed : iface->ia_addr;
256 size_t addrlen = (c->managed) ? (size_t)c->managed_size : iface->ia_addr_len;
259 for (size_t i = 0; i < addrlen; ++i)
260 if (addrs[i].preferred > addrs[mostpref].preferred)
263 for (size_t i = 0; i < addrlen; ++i) {
264 if (addrs[i].prefix > 96 || c->valid_until <= now ||
265 (iface->managed < RELAYD_MANAGED_NO_AFLAG && i != mostpref))
268 addr = addrs[i].addr;
269 if (c->length == 128)
270 addr.s6_addr32[3] = htonl(c->assigned);
272 addr.s6_addr32[1] |= htonl(c->assigned);
274 inet_ntop(AF_INET6, &addr, ipbuf, sizeof(ipbuf) - 1);
276 if (c->length == 128 && c->hostname) {
280 if (dn_expand(iface->search, iface->search + iface->search_len,
281 iface->search, b, sizeof(b)) > 0)
282 fprintf(fp, "\t%s.%s", c->hostname, b);
284 fprintf(fp, "\t%s\n", c->hostname);
285 md5_hash(ipbuf, strlen(ipbuf), &md5);
286 md5_hash(c->hostname, strlen(c->hostname), &md5);
289 l += snprintf(leasebuf + l, sizeof(leasebuf) - l, "%s/%d ", ipbuf,
290 (c->managed_size) ? addrs[i].prefix : c->length);
292 leasebuf[l - 1] = '\n';
293 fwrite(leasebuf, 1, l, fp);
297 if (iface->dhcpv4 == RELAYD_SERVER && iface->dhcpv4_assignments.next) {
298 struct dhcpv4_assignment *c;
299 list_for_each_entry(c, &iface->dhcpv4_assignments, head) {
300 char ipbuf[INET6_ADDRSTRLEN];
303 odhcpd_hexlify(duidbuf, c->hwaddr, sizeof(c->hwaddr));
305 // iface DUID iaid hostname lifetime assigned length [addrs...]
306 int l = snprintf(leasebuf, sizeof(leasebuf), "# %s %s ipv4 %s %u %x 32 ",
307 iface->ifname, duidbuf,
308 (c->hostname ? c->hostname : "-"),
309 (unsigned)(c->valid_until > now ?
310 (c->valid_until - now + wall_time) : 0),
313 struct in_addr addr = {htonl(c->addr)};
314 inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf) - 1);
316 if (c->hostname[0]) {
320 if (dn_expand(iface->search, iface->search + iface->search_len,
321 iface->search, b, sizeof(b)) > 0)
322 fprintf(fp, "\t%s.%s", c->hostname, b);
324 fprintf(fp, "\t%s\n", c->hostname);
325 md5_hash(ipbuf, strlen(ipbuf), &md5);
326 md5_hash(c->hostname, strlen(c->hostname), &md5);
329 l += snprintf(leasebuf + l, sizeof(leasebuf) - l, "%s/32 ", ipbuf);
330 leasebuf[l - 1] = '\n';
331 fwrite(leasebuf, 1, l, fp);
340 md5_end(newmd5, &md5);
342 if (config.dhcp_cb && memcmp(newmd5, statemd5, sizeof(newmd5))) {
343 memcpy(statemd5, newmd5, sizeof(statemd5));
344 char *argv[2] = {config.dhcp_cb, NULL};
346 execv(argv[0], argv);
353 static void apply_lease(struct interface *iface, struct dhcpv6_assignment *a, bool add)
355 if (a->length > 64 || a->managed_size < 0)
358 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
359 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
361 for (size_t i = 0; i < addrlen; ++i) {
362 struct in6_addr prefix = addrs[i].addr;
363 prefix.s6_addr32[1] |= htonl(a->assigned);
364 odhcpd_setup_route(&prefix, (a->managed_size) ? addrs[i].prefix : a->length,
365 iface, &a->peer.sin6_addr, add);
370 // More data was received from TCP connection
371 static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
373 struct dhcpv6_assignment *c = container_of(s, struct dhcpv6_assignment, managed_sock);
374 time_t now = odhcpd_time();
375 bool first = c->managed_size < 0;
379 char *data = ustream_get_read_buf(s, &pending);
380 char *end = memmem(data, pending, "\n\n", 2);
389 if (c->accept_reconf)
393 for (char *line = strtok_r(data, "\n", &saveptr); line; line = strtok_r(NULL, "\n", &saveptr)) {
394 c->managed = realloc(c->managed, (c->managed_size + 1) * sizeof(*c->managed));
395 struct odhcpd_ipaddr *n = &c->managed[c->managed_size];
397 char *saveptr2, *x = strtok_r(line, "/", &saveptr2);
398 if (!x || inet_pton(AF_INET6, x, &n->addr) < 1)
401 x = strtok_r(NULL, ",", &saveptr2);
402 if (sscanf(x, "%hhu", &n->prefix) < 1)
405 x = strtok_r(NULL, ",", &saveptr2);
406 if (sscanf(x, "%u", &n->preferred) < 1)
409 x = strtok_r(NULL, ",", &saveptr2);
410 if (sscanf(x, "%u", &n->valid) < 1)
413 if (n->preferred > n->valid)
416 if (UINT32_MAX - now < n->preferred)
417 n->preferred = UINT32_MAX;
421 if (UINT32_MAX - now < n->valid)
422 n->valid = UINT32_MAX;
431 ustream_consume(s, end - data);
434 if (first && c->managed_size == 0)
435 free_dhcpv6_assignment(c);
437 c->valid_until = now + 150;
441 // TCP transmission has ended, either because of success or timeout or other error
442 static void managed_handle_pd_done(struct ustream *s)
444 struct dhcpv6_assignment *c = container_of(s, struct dhcpv6_assignment, managed_sock);
445 c->valid_until = odhcpd_time() + 15;
447 if (c->accept_reconf)
453 static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
455 struct dhcpv6_assignment *c;
457 if (iface->dhcpv6_pd_manager[0]) {
458 int fd = usock(USOCK_UNIX | USOCK_TCP, iface->dhcpv6_pd_manager, NULL);
461 odhcpd_hexlify(iaidbuf, assign->clid_data, assign->clid_len);
463 assign->managed_sock.stream.notify_read = managed_handle_pd_data;
464 assign->managed_sock.stream.notify_state = managed_handle_pd_done;
465 ustream_fd_init(&assign->managed_sock, fd);
466 ustream_printf(&assign->managed_sock.stream, "%s,%x\n::/%d,0,0\n\n",
467 iaidbuf, assign->iaid, assign->length);
468 ustream_write_pending(&assign->managed_sock.stream);
469 assign->managed_size = -1;
470 assign->valid_until = odhcpd_time() + 15;
471 list_add(&assign->head, &iface->ia_assignments);
473 // Wait initial period of up to 250ms for immediate assignment
474 struct pollfd pfd = { .fd = fd, .events = POLLIN };
476 managed_handle_pd_data(&assign->managed_sock.stream, 0);
478 if (fcntl(fd, F_GETFL) >= 0 && assign->managed_size > 0)
483 } else if (iface->ia_addr_len < 1) {
487 // Try honoring the hint first
488 uint32_t current = 1, asize = (1 << (64 - assign->length)) - 1;
489 if (assign->assigned) {
490 list_for_each_entry(c, &iface->ia_assignments, head) {
491 if (c->length == 128 || c->length == 0)
494 if (assign->assigned >= current && assign->assigned + asize < c->assigned) {
495 list_add_tail(&assign->head, &c->head);
496 apply_lease(iface, assign, true);
500 if (c->assigned != 0)
501 current = (c->assigned + (1 << (64 - c->length)));
505 // Fallback to a variable assignment
507 list_for_each_entry(c, &iface->ia_assignments, head) {
508 if (c->length == 128 || c->length == 0)
511 current = (current + asize) & (~asize);
512 if (current + asize < c->assigned) {
513 assign->assigned = current;
514 list_add_tail(&assign->head, &c->head);
515 apply_lease(iface, assign, true);
519 if (c->assigned != 0)
520 current = (c->assigned + (1 << (64 - c->length)));
527 static bool assign_na(struct interface *iface, struct dhcpv6_assignment *assign)
529 // Seed RNG with checksum of DUID
531 for (size_t i = 0; i < assign->clid_len; ++i)
532 seed += assign->clid_data[i];
535 // Try to assign up to 100x
536 for (size_t i = 0; i < 100; ++i) {
538 do try = ((uint32_t)rand()) % 0x0fff; while (try < 0x100);
540 struct dhcpv6_assignment *c;
541 list_for_each_entry(c, &iface->ia_assignments, head) {
545 if (c->assigned > try || c->length != 128) {
546 assign->assigned = try;
547 list_add_tail(&assign->head, &c->head);
549 } else if (c->assigned == try) {
559 static int prefixcmp(const void *va, const void *vb)
561 const struct odhcpd_ipaddr *a = va, *b = vb;
562 uint32_t a_pref = ((a->addr.s6_addr[0] & 0xfe) != 0xfc) ? a->preferred : 1;
563 uint32_t b_pref = ((b->addr.s6_addr[0] & 0xfe) != 0xfc) ? b->preferred : 1;
564 return (a_pref < b_pref) ? 1 : (a_pref > b_pref) ? -1 : 0;
568 static void update(struct interface *iface)
570 struct odhcpd_ipaddr addr[8];
571 memset(addr, 0, sizeof(addr));
572 int len = odhcpd_get_interface_addresses(iface->ifindex, addr, 8);
577 qsort(addr, len, sizeof(*addr), prefixcmp);
579 time_t now = odhcpd_time();
582 for (int i = 0; i < len; ++i) {
583 if (addr[i].preferred > 0 && addr[i].prefix > minprefix)
584 minprefix = addr[i].prefix;
586 addr[i].addr.s6_addr32[3] = 0;
588 if (addr[i].preferred < UINT32_MAX - now)
589 addr[i].preferred += now;
591 if (addr[i].valid < UINT32_MAX - now)
592 addr[i].valid += now;
595 struct dhcpv6_assignment *border = list_last_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
596 border->assigned = 1 << (64 - minprefix);
598 bool change = len != (int)iface->ia_addr_len;
599 for (int i = 0; !change && i < len; ++i)
600 if (addr[i].addr.s6_addr32[0] != iface->ia_addr[i].addr.s6_addr32[0] ||
601 addr[i].addr.s6_addr32[1] != iface->ia_addr[i].addr.s6_addr32[1] ||
602 (addr[i].preferred > 0) != (iface->ia_addr[i].preferred > 0) ||
603 (addr[i].valid > (uint32_t)now + 7200) !=
604 (iface->ia_addr[i].valid > (uint32_t)now + 7200))
608 struct dhcpv6_assignment *c;
609 list_for_each_entry(c, &iface->ia_assignments, head)
610 if (c != border && !iface->managed)
611 apply_lease(iface, c, false);
614 memcpy(iface->ia_addr, addr, len * sizeof(*addr));
615 iface->ia_addr_len = len;
617 if (change) { // Addresses / prefixes have changed
618 struct list_head reassign = LIST_HEAD_INIT(reassign);
619 struct dhcpv6_assignment *c, *d;
620 list_for_each_entry_safe(c, d, &iface->ia_assignments, head) {
621 if (c->clid_len == 0 || c->valid_until < now || c->managed_size)
624 if (c->length < 128 && c->assigned >= border->assigned && c != border)
625 list_move(&c->head, &reassign);
626 else if (c != border)
627 apply_lease(iface, c, true);
629 if (c->accept_reconf && c->reconf_cnt == 0) {
631 c->reconf_sent = now;
632 send_reconf(iface, c);
634 // Leave all other assignments of that client alone
635 struct dhcpv6_assignment *a;
636 list_for_each_entry(a, &iface->ia_assignments, head)
637 if (a != c && a->clid_len == c->clid_len &&
638 !memcmp(a->clid_data, c->clid_data, a->clid_len))
639 c->reconf_cnt = INT_MAX;
643 while (!list_empty(&reassign)) {
644 c = list_first_entry(&reassign, struct dhcpv6_assignment, head);
646 if (!assign_pd(iface, c)) {
648 list_add(&c->head, &iface->ia_assignments);
652 dhcpv6_write_statefile();
657 static void reconf_timer(struct uloop_timeout *event)
659 time_t now = odhcpd_time();
660 struct interface *iface;
661 list_for_each_entry(iface, &interfaces, head) {
662 if (iface->dhcpv6 != RELAYD_SERVER || iface->ia_assignments.next == NULL)
665 struct dhcpv6_assignment *a, *n;
666 list_for_each_entry_safe(a, n, &iface->ia_assignments, head) {
667 if (a->valid_until < now) {
668 if ((a->length < 128 && a->clid_len > 0) ||
669 (a->length == 128 && a->clid_len == 0)) {
671 free_dhcpv6_assignment(a);
673 } else if (a->reconf_cnt > 0 && a->reconf_cnt < 8 &&
674 now > a->reconf_sent + (1 << a->reconf_cnt)) {
676 a->reconf_sent = now;
677 send_reconf(iface, a);
681 uloop_timeout_set(event, 2000);
685 static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
686 const struct dhcpv6_ia_hdr *ia, struct dhcpv6_assignment *a,
687 struct interface *iface, bool request)
689 if (buflen < sizeof(*ia) + sizeof(struct dhcpv6_ia_prefix))
692 struct dhcpv6_ia_hdr out = {ia->type, 0, ia->iaid, 0, 0};
693 size_t datalen = sizeof(out);
694 time_t now = odhcpd_time();
697 struct __attribute__((packed)) {
701 } stat = {htons(DHCPV6_OPT_STATUS), htons(sizeof(stat) - 4),
704 memcpy(buf + datalen, &stat, sizeof(stat));
705 datalen += sizeof(stat);
708 uint32_t leasetime = iface->dhcpv4_leasetime;
711 else if (leasetime < 60)
714 uint32_t pref = leasetime;
715 uint32_t valid = leasetime;
717 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
718 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
721 for (size_t i = 0; i < addrlen; ++i)
722 if (addrs[i].preferred > addrs[mostpref].preferred)
725 for (size_t i = 0; i < addrlen; ++i) {
726 uint32_t prefix_pref = addrs[i].preferred - now;
727 uint32_t prefix_valid = addrs[i].valid - now;
729 if (addrs[i].prefix > 96 ||
730 addrs[i].preferred <= (uint32_t)now)
733 if (a->length < 128) {
734 struct dhcpv6_ia_prefix p = {
735 .type = htons(DHCPV6_OPT_IA_PREFIX),
736 .len = htons(sizeof(p) - 4),
737 .preferred = htonl(prefix_pref),
738 .valid = htonl(prefix_valid),
739 .prefix = (a->managed_size) ? addrs[i].prefix : a->length,
740 .addr = addrs[i].addr
742 p.addr.s6_addr32[1] |= htonl(a->assigned);
744 size_t entrlen = sizeof(p) - 4;
746 if (datalen + entrlen + 4 > buflen ||
747 (a->assigned == 0 && a->managed_size == 0))
750 memcpy(buf + datalen, &p, sizeof(p));
751 datalen += entrlen + 4;
753 struct dhcpv6_ia_addr n = {
754 .type = htons(DHCPV6_OPT_IA_ADDR),
755 .len = htons(sizeof(n) - 4),
756 .addr = addrs[i].addr,
757 .preferred = htonl(prefix_pref),
758 .valid = htonl(prefix_valid)
760 n.addr.s6_addr32[3] = htonl(a->assigned);
761 size_t entrlen = sizeof(n) - 4;
763 if (iface->managed < RELAYD_MANAGED_NO_AFLAG && i != mostpref)
766 if (datalen + entrlen + 4 > buflen || a->assigned == 0)
769 memcpy(buf + datalen, &n, sizeof(n));
770 datalen += entrlen + 4;
773 // Calculate T1 / T2 based on non-deprecated addresses
774 if (prefix_pref > 0) {
775 if (prefix_pref < pref)
778 if (prefix_valid < valid)
779 valid = prefix_valid;
783 a->valid_until = valid + now;
784 out.t1 = htonl(pref * 5 / 10);
785 out.t2 = htonl(pref * 8 / 10);
795 uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
796 uint16_t otype, olen;
797 dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
798 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&odata[-4];
799 struct dhcpv6_ia_addr *n = (struct dhcpv6_ia_addr*)&odata[-4];
800 if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*p) - 4) &&
801 (otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*n) - 4))
806 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
807 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
809 for (size_t i = 0; i < addrlen; ++i) {
810 if (addrs[i].prefix > 96 ||
811 addrs[i].preferred <= (uint32_t)now)
814 struct in6_addr addr = addrs[i].addr;
815 if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
816 addr.s6_addr32[1] |= htonl(a->assigned);
818 if (!memcmp(&p->addr, &addr, sizeof(addr)) &&
819 p->prefix == ((a->managed) ? addrs[i].prefix : a->length))
822 addr.s6_addr32[3] = htonl(a->assigned);
824 if (!memcmp(&n->addr, &addr, sizeof(addr)))
831 if (otype == DHCPV6_OPT_IA_PREFIX) {
832 struct dhcpv6_ia_prefix inv = {
833 .type = htons(DHCPV6_OPT_IA_PREFIX),
834 .len = htons(sizeof(inv) - 4),
841 if (datalen + sizeof(inv) > buflen)
844 memcpy(buf + datalen, &inv, sizeof(inv));
845 datalen += sizeof(inv);
847 struct dhcpv6_ia_addr inv = {
848 .type = htons(DHCPV6_OPT_IA_ADDR),
849 .len = htons(sizeof(inv) - 4),
855 if (datalen + sizeof(inv) > buflen)
858 memcpy(buf + datalen, &inv, sizeof(inv));
859 datalen += sizeof(inv);
866 out.len = htons(datalen - 4);
867 memcpy(buf, &out, sizeof(out));
872 static void dhcpv6_log(uint8_t msgtype, struct interface *iface, time_t now,
873 const char *duidbuf, bool is_pd, struct dhcpv6_assignment *a, int code)
875 const char *type = "UNKNOWN";
876 const char *status = "UNKNOWN";
878 if (msgtype == DHCPV6_MSG_RENEW)
882 case DHCPV6_MSG_SOLICIT:
885 case DHCPV6_MSG_REQUEST:
888 case DHCPV6_MSG_CONFIRM:
891 case DHCPV6_MSG_RENEW:
894 case DHCPV6_MSG_REBIND:
897 case DHCPV6_MSG_RELEASE:
900 case DHCPV6_MSG_DECLINE:
906 case DHCPV6_STATUS_OK:
909 case DHCPV6_STATUS_NOADDRSAVAIL:
910 status = "no addresses available";
912 case DHCPV6_STATUS_NOBINDING:
913 status = "no binding";
915 case DHCPV6_STATUS_NOTONLINK:
916 status = "not on-link";
918 case DHCPV6_STATUS_NOPREFIXAVAIL:
919 status = "no prefix available";
923 char leasebuf[256] = "";
926 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
927 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
929 char addrbuf[INET6_ADDRSTRLEN];
931 for (size_t i = 0; i < addrlen; ++i) {
932 if (addrs[i].prefix > 96 || addrs[i].preferred <= (uint32_t)now)
935 struct in6_addr addr = addrs[i].addr;
936 int prefix = a->managed ? addrs[i].prefix : a->length;
938 addr.s6_addr32[3] = htonl(a->assigned);
940 addr.s6_addr32[1] |= htonl(a->assigned);
942 inet_ntop(AF_INET6, &addr, addrbuf, sizeof(addrbuf));
943 lbsize += snprintf(leasebuf + lbsize, sizeof(leasebuf) - lbsize, "%s/%d ", addrbuf, prefix);
947 syslog(LOG_WARNING, "DHCPV6 %s %s from %s on %s: %s %s", type, (is_pd) ? "IA_PD" : "IA_NA",
948 duidbuf, iface->ifname, status, leasebuf);
953 ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
954 const struct sockaddr_in6 *addr, const void *data, const uint8_t *end)
956 time_t now = odhcpd_time();
957 size_t response_len = 0;
958 const struct dhcpv6_client_header *hdr = data;
959 uint8_t *start = (uint8_t*)&hdr[1], *odata;
960 uint16_t otype, olen;
962 // Find and parse client-id and hostname
963 bool accept_reconf = false;
964 uint8_t *clid_data = NULL, clid_len = 0, mac[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
966 size_t hostname_len = 0;
967 bool notonlink = false;
970 dhcpv6_for_each_option(start, end, otype, olen, odata) {
971 if (otype == DHCPV6_OPT_CLIENTID) {
975 if (olen == 14 && odata[0] == 0 && odata[1] == 1)
976 memcpy(mac, &odata[8], sizeof(mac));
977 else if (olen == 10 && odata[0] == 0 && odata[1] == 3)
978 memcpy(mac, &odata[4], sizeof(mac));
981 odhcpd_hexlify(duidbuf, odata, olen);
982 } else if (otype == DHCPV6_OPT_FQDN && olen >= 2 && olen <= 255) {
983 uint8_t fqdn_buf[256];
984 memcpy(fqdn_buf, odata, olen);
985 fqdn_buf[olen++] = 0;
987 if (dn_expand(&fqdn_buf[1], &fqdn_buf[olen], &fqdn_buf[1], hostname, sizeof(hostname)) > 0)
988 hostname_len = strcspn(hostname, ".");
989 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
990 accept_reconf = true;
994 if (!clid_data || !clid_len || clid_len > 130)
999 struct dhcpv6_assignment *first = NULL;
1000 dhcpv6_for_each_option(start, end, otype, olen, odata) {
1001 bool is_pd = (otype == DHCPV6_OPT_IA_PD);
1002 bool is_na = (otype == DHCPV6_OPT_IA_NA);
1003 bool ia_addr_present = false;
1004 if (!is_pd && !is_na)
1007 struct dhcpv6_ia_hdr *ia = (struct dhcpv6_ia_hdr*)&odata[-4];
1008 size_t ia_response_len = 0;
1009 uint8_t reqlen = (is_pd) ? 62 : 128;
1010 uint32_t reqhint = 0;
1012 // Parse request hint for IA-PD
1015 uint16_t stype, slen;
1016 dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1017 if (stype != DHCPV6_OPT_IA_PREFIX || slen < sizeof(struct dhcpv6_ia_prefix) - 4)
1020 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&sdata[-4];
1023 reqhint = ntohl(p->addr.s6_addr32[1]);
1024 if (reqlen > 32 && reqlen <= 64)
1025 reqhint &= (1U << (64 - reqlen)) - 1;
1033 uint16_t stype, slen;
1034 dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1035 if (stype != DHCPV6_OPT_IA_ADDR || slen < sizeof(struct dhcpv6_ia_addr) - 4)
1038 ia_addr_present = true;
1043 struct dhcpv6_assignment *c, *a = NULL;
1044 list_for_each_entry(c, &iface->ia_assignments, head) {
1045 if (((c->clid_len == clid_len && !memcmp(c->clid_data, clid_data, clid_len)) ||
1046 (c->clid_len >= clid_len && !c->clid_data[0] && !c->clid_data[1]
1047 && !memcmp(c->mac, mac, sizeof(mac)))) &&
1048 (c->iaid == ia->iaid || c->valid_until < now) &&
1049 ((is_pd && c->length <= 64) || (is_na && c->length == 128))) {
1053 apply_lease(iface, a, false);
1054 memcpy(a->clid_data, clid_data, clid_len);
1055 a->clid_len = clid_len;
1064 // Generic message handling
1065 uint16_t status = DHCPV6_STATUS_OK;
1066 if (a && a->managed_size < 0) {
1068 } else if (hdr->msg_type == DHCPV6_MSG_SOLICIT || hdr->msg_type == DHCPV6_MSG_REQUEST) {
1069 bool assigned = !!a;
1071 if (!a && !iface->no_dynamic_dhcp) { // Create new binding
1072 a = calloc(1, sizeof(*a) + clid_len);
1074 a->clid_len = clid_len;
1078 a->assigned = reqhint;
1081 memcpy(a->key, first->key, sizeof(a->key));
1083 odhcpd_urandom(a->key, sizeof(a->key));
1084 memcpy(a->clid_data, clid_data, clid_len);
1087 while (!(assigned = assign_pd(iface, a)) &&
1088 !a->managed_size && ++a->length <= 64);
1090 assigned = assign_na(iface, a);
1092 if (a->managed_size && !assigned)
1097 if (!assigned || iface->ia_addr_len == 0) { // Set error status
1098 status = (is_pd) ? DHCPV6_STATUS_NOPREFIXAVAIL : DHCPV6_STATUS_NOADDRSAVAIL;
1099 } else if (assigned && !first) { //
1100 size_t handshake_len = 4;
1102 buf[1] = DHCPV6_OPT_RECONF_ACCEPT;
1106 if (hdr->msg_type == DHCPV6_MSG_REQUEST) {
1107 struct dhcpv6_auth_reconfigure auth = {
1108 htons(DHCPV6_OPT_AUTH),
1109 htons(sizeof(auth) - 4),
1111 {htonl(time(NULL)), htonl(++serial)},
1115 memcpy(auth.key, a->key, sizeof(a->key));
1116 memcpy(buf + handshake_len, &auth, sizeof(auth));
1117 handshake_len += sizeof(auth);
1120 buf += handshake_len;
1121 buflen -= handshake_len;
1122 response_len += handshake_len;
1127 ia_response_len = append_reply(buf, buflen, status, ia, a, iface, true);
1129 // Was only a solicitation: mark binding for removal
1130 if (assigned && hdr->msg_type == DHCPV6_MSG_SOLICIT) {
1132 } else if (assigned && hdr->msg_type == DHCPV6_MSG_REQUEST) {
1133 if (hostname_len > 0) {
1134 a->hostname = realloc(a->hostname, hostname_len + 1);
1136 memcpy(a->hostname, hostname, hostname_len);
1137 a->hostname[hostname_len] = 0;
1140 a->accept_reconf = accept_reconf;
1141 apply_lease(iface, a, true);
1142 } else if (!assigned && a && a->managed_size == 0) { // Cleanup failed assignment
1143 free_dhcpv6_assignment(a);
1145 } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1146 hdr->msg_type == DHCPV6_MSG_RELEASE ||
1147 hdr->msg_type == DHCPV6_MSG_REBIND ||
1148 hdr->msg_type == DHCPV6_MSG_DECLINE) {
1149 if (!a && hdr->msg_type != DHCPV6_MSG_REBIND) {
1150 status = DHCPV6_STATUS_NOBINDING;
1151 ia_response_len = append_reply(buf, buflen, status, ia, a, iface, false);
1152 } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1153 hdr->msg_type == DHCPV6_MSG_REBIND) {
1154 ia_response_len = append_reply(buf, buflen, status, ia, a, iface, false);
1156 apply_lease(iface, a, true);
1157 } else if (hdr->msg_type == DHCPV6_MSG_RELEASE) {
1159 apply_lease(iface, a, false);
1160 } else if (hdr->msg_type == DHCPV6_MSG_DECLINE && a->length == 128) {
1162 a->valid_until = now + 3600; // Block address for 1h
1164 } else if (hdr->msg_type == DHCPV6_MSG_CONFIRM && ia_addr_present) {
1165 // Send NOTONLINK for CONFIRM with addr present so that clients restart connection
1166 status = DHCPV6_STATUS_NOTONLINK;
1167 ia_response_len = append_reply(buf, buflen, status, ia, a, iface, true);
1171 buf += ia_response_len;
1172 buflen -= ia_response_len;
1173 response_len += ia_response_len;
1174 dhcpv6_log(hdr->msg_type, iface, now, duidbuf, is_pd, a, status);
1177 if ((hdr->msg_type == DHCPV6_MSG_RELEASE || hdr->msg_type == DHCPV6_MSG_DECLINE || notonlink) &&
1178 response_len + 6 < buflen) {
1180 buf[1] = DHCPV6_OPT_STATUS;
1184 buf[5] = (notonlink) ? DHCPV6_STATUS_NOTONLINK : DHCPV6_STATUS_OK;
1188 dhcpv6_write_statefile();
1191 return response_len;