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dhcp: rework static lease logic
[project/odhcpd.git] / src / dhcpv6-ia.c
1 /**
2 * Copyright (C) 2013 Steven Barth <steven@midlink.org>
3 * Copyright (C) 2016 Hans Dedecker <dedeckeh@gmail.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License v2 as published by
7 * the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 */
15
16 #include "odhcpd.h"
17 #include "dhcpv6.h"
18 #include "dhcpv4.h"
19
20 #include <time.h>
21 #include <errno.h>
22 #include <fcntl.h>
23 #include <stdio.h>
24 #include <poll.h>
25 #include <alloca.h>
26 #include <resolv.h>
27 #include <limits.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <unistd.h>
31 #include <stdbool.h>
32 #include <arpa/inet.h>
33 #include <sys/timerfd.h>
34
35 #include <libubox/md5.h>
36 #include <libubox/usock.h>
37
38 #define ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) \
39 ((iface)->dhcpv6_assignall || (i) == (m) || \
40 (addrs)[(i)].prefix > 64)
41
42 static void dhcpv6_netevent_cb(unsigned long event, struct netevent_handler_info *info);
43 static void set_border_assignment_size(struct interface *iface, struct dhcp_assignment *b);
44 static void handle_addrlist_change(struct netevent_handler_info *info);
45 static void start_reconf(struct dhcp_assignment *a);
46 static void stop_reconf(struct dhcp_assignment *a);
47 static void valid_until_cb(struct uloop_timeout *event);
48
49 static struct netevent_handler dhcpv6_netevent_handler = { .cb = dhcpv6_netevent_cb, };
50 static struct uloop_timeout valid_until_timeout = {.cb = valid_until_cb};
51 static uint32_t serial = 0;
52 static uint8_t statemd5[16];
53
54 int dhcpv6_ia_init(void)
55 {
56 uloop_timeout_set(&valid_until_timeout, 1000);
57
58 netlink_add_netevent_handler(&dhcpv6_netevent_handler);
59
60 return 0;
61 }
62
63 int dhcpv6_ia_setup_interface(struct interface *iface, bool enable)
64 {
65 if (!enable && iface->ia_assignments.next) {
66 struct dhcp_assignment *c;
67
68 while (!list_empty(&iface->ia_assignments)) {
69 c = list_first_entry(&iface->ia_assignments, struct dhcp_assignment, head);
70 dhcpv6_ia_free_assignment(c);
71 }
72 }
73
74 if (enable && iface->dhcpv6 == MODE_SERVER) {
75 struct dhcp_assignment *border;
76
77 if (!iface->ia_assignments.next)
78 INIT_LIST_HEAD(&iface->ia_assignments);
79
80 if (list_empty(&iface->ia_assignments)) {
81 border = calloc(1, sizeof(*border));
82
83 if (!border) {
84 syslog(LOG_ERR, "Calloc failed for border on %s", iface->name);
85 return -1;
86 }
87
88 border->length = 64;
89 list_add(&border->head, &iface->ia_assignments);
90 } else
91 border = list_last_entry(&iface->ia_assignments, struct dhcp_assignment, head);
92
93 set_border_assignment_size(iface, border);
94 }
95 return 0;
96 }
97
98
99 static void dhcpv6_netevent_cb(unsigned long event, struct netevent_handler_info *info)
100 {
101 struct interface *iface = info->iface;
102
103 if (!iface || iface->dhcpv6 != MODE_SERVER)
104 return;
105
106 switch (event) {
107 case NETEV_ADDR6LIST_CHANGE:
108 handle_addrlist_change(info);
109 break;
110 default:
111 break;
112 }
113 }
114
115
116 static inline bool valid_prefix_length(const struct dhcp_assignment *a, const uint8_t prefix_length)
117 {
118 return (a->managed_size || a->length > prefix_length);
119 }
120
121 static inline bool valid_addr(const struct odhcpd_ipaddr *addr, time_t now)
122 {
123 return (addr->prefix <= 96 && addr->preferred > (uint32_t)now);
124 }
125
126 static size_t get_preferred_addr(const struct odhcpd_ipaddr *addrs, const size_t addrlen)
127 {
128 size_t i, m;
129
130 for (i = 0, m = 0; i < addrlen; ++i) {
131 if (addrs[i].preferred > addrs[m].preferred ||
132 (addrs[i].preferred == addrs[m].preferred &&
133 memcmp(&addrs[i].addr, &addrs[m].addr, 16) > 0))
134 m = i;
135 }
136
137 return m;
138 }
139
140 static int send_reconf(struct dhcp_assignment *assign)
141 {
142 struct {
143 struct dhcpv6_client_header hdr;
144 uint16_t srvid_type;
145 uint16_t srvid_len;
146 uint16_t duid_type;
147 uint16_t hardware_type;
148 uint8_t mac[6];
149 uint16_t msg_type;
150 uint16_t msg_len;
151 uint8_t msg_id;
152 struct dhcpv6_auth_reconfigure auth;
153 uint16_t clid_type;
154 uint16_t clid_len;
155 uint8_t clid_data[128];
156 } __attribute__((packed)) reconf_msg = {
157 .hdr = {DHCPV6_MSG_RECONFIGURE, {0, 0, 0}},
158 .srvid_type = htons(DHCPV6_OPT_SERVERID),
159 .srvid_len = htons(10),
160 .duid_type = htons(3),
161 .hardware_type = htons(1),
162 .msg_type = htons(DHCPV6_OPT_RECONF_MSG),
163 .msg_len = htons(1),
164 .msg_id = DHCPV6_MSG_RENEW,
165 .auth = {htons(DHCPV6_OPT_AUTH),
166 htons(sizeof(reconf_msg.auth) - 4), 3, 1, 0,
167 {htonl(time(NULL)), htonl(++serial)}, 2, {0}},
168 .clid_type = htons(DHCPV6_OPT_CLIENTID),
169 .clid_len = htons(assign->clid_len),
170 .clid_data = {0},
171 };
172 struct interface *iface = assign->iface;
173
174 odhcpd_get_mac(iface, reconf_msg.mac);
175 memcpy(reconf_msg.clid_data, assign->clid_data, assign->clid_len);
176 struct iovec iov = {&reconf_msg, sizeof(reconf_msg) - 128 + assign->clid_len};
177
178 md5_ctx_t md5;
179 uint8_t secretbytes[64];
180 memset(secretbytes, 0, sizeof(secretbytes));
181 memcpy(secretbytes, assign->key, sizeof(assign->key));
182
183 for (size_t i = 0; i < sizeof(secretbytes); ++i)
184 secretbytes[i] ^= 0x36;
185
186 md5_begin(&md5);
187 md5_hash(secretbytes, sizeof(secretbytes), &md5);
188 md5_hash(iov.iov_base, iov.iov_len, &md5);
189 md5_end(reconf_msg.auth.key, &md5);
190
191 for (size_t i = 0; i < sizeof(secretbytes); ++i) {
192 secretbytes[i] ^= 0x36;
193 secretbytes[i] ^= 0x5c;
194 }
195
196 md5_begin(&md5);
197 md5_hash(secretbytes, sizeof(secretbytes), &md5);
198 md5_hash(reconf_msg.auth.key, 16, &md5);
199 md5_end(reconf_msg.auth.key, &md5);
200
201 return odhcpd_send(iface->dhcpv6_event.uloop.fd, &assign->peer, &iov, 1, iface);
202 }
203
204 void dhcpv6_ia_free_assignment(struct dhcp_assignment *a)
205 {
206 if (a->managed_sock.fd.registered) {
207 ustream_free(&a->managed_sock.stream);
208 close(a->managed_sock.fd.fd);
209 }
210
211 if (a->head.next)
212 list_del(&a->head);
213
214 if (a->lease_list.next)
215 list_del(&a->lease_list);
216
217 if (a->reconf_cnt)
218 stop_reconf(a);
219
220 free(a->managed);
221 free(a->hostname);
222 free(a);
223 }
224
225 void dhcpv6_ia_enum_addrs(struct interface *iface, struct dhcp_assignment *c,
226 time_t now, dhcpv6_binding_cb_handler_t func, void *arg)
227 {
228 struct odhcpd_ipaddr *addrs = (c->managed) ? c->managed : iface->addr6;
229 size_t addrlen = (c->managed) ? (size_t)c->managed_size : iface->addr6_len;
230 size_t m = get_preferred_addr(addrs, addrlen);
231
232 for (size_t i = 0; i < addrlen; ++i) {
233 struct in6_addr addr;
234 uint32_t pref, valid;
235 int prefix = c->managed ? addrs[i].prefix : c->length;
236
237 if (!valid_addr(&addrs[i], now))
238 continue;
239
240 addr = addrs[i].addr.in6;
241 pref = addrs[i].preferred;
242 valid = addrs[i].valid;
243 if (prefix == 128) {
244 if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs))
245 continue;
246
247 addr.s6_addr32[3] = htonl(c->assigned);
248 } else {
249 if (!valid_prefix_length(c, addrs[i].prefix))
250 continue;
251
252 addr.s6_addr32[1] |= htonl(c->assigned);
253 addr.s6_addr32[2] = addr.s6_addr32[3] = 0;
254 }
255
256 if (pref != UINT32_MAX)
257 pref -= now;
258
259 if (valid != UINT32_MAX)
260 valid -= now;
261
262 func(&addr, prefix, pref, valid, arg);
263 }
264 }
265
266 struct write_ctxt {
267 FILE *fp;
268 md5_ctx_t md5;
269 struct dhcp_assignment *c;
270 struct interface *iface;
271 char *buf;
272 int buf_len;
273 int buf_idx;
274 };
275
276 void dhcpv6_write_ia_addr(struct in6_addr *addr, int prefix, _unused uint32_t pref,
277 _unused uint32_t valid, void *arg)
278 {
279 struct write_ctxt *ctxt = (struct write_ctxt *)arg;
280 char ipbuf[INET6_ADDRSTRLEN];
281
282 inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf) - 1);
283
284 if (ctxt->c->length == 128 && ctxt->c->hostname &&
285 !(ctxt->c->flags & OAF_BROKEN_HOSTNAME)) {
286 fputs(ipbuf, ctxt->fp);
287
288 char b[256];
289 if (dn_expand(ctxt->iface->search, ctxt->iface->search + ctxt->iface->search_len,
290 ctxt->iface->search, b, sizeof(b)) > 0)
291 fprintf(ctxt->fp, "\t%s.%s", ctxt->c->hostname, b);
292
293 fprintf(ctxt->fp, "\t%s\n", ctxt->c->hostname);
294 md5_hash(ipbuf, strlen(ipbuf), &ctxt->md5);
295 md5_hash(ctxt->c->hostname, strlen(ctxt->c->hostname), &ctxt->md5);
296 }
297
298 ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx,ctxt->buf_len - ctxt->buf_idx,
299 "%s/%d ", ipbuf, prefix);
300 }
301
302 void dhcpv6_ia_write_statefile(void)
303 {
304 struct write_ctxt ctxt;
305
306 md5_begin(&ctxt.md5);
307
308 if (config.dhcp_statefile) {
309 time_t now = odhcpd_time(), wall_time = time(NULL);
310 int fd = open(config.dhcp_statefile, O_CREAT | O_WRONLY | O_CLOEXEC, 0644);
311 char leasebuf[512];
312
313 if (fd < 0)
314 return;
315 int ret;
316 ret = lockf(fd, F_LOCK, 0);
317 if (ret < 0) {
318 close(fd);
319 return;
320 }
321 if (ftruncate(fd, 0) < 0) {}
322
323 ctxt.fp = fdopen(fd, "w");
324 if (!ctxt.fp) {
325 close(fd);
326 return;
327 }
328
329 ctxt.buf = leasebuf;
330 ctxt.buf_len = sizeof(leasebuf);
331
332 avl_for_each_element(&interfaces, ctxt.iface, avl) {
333 if (ctxt.iface->dhcpv6 != MODE_SERVER &&
334 ctxt.iface->dhcpv4 != MODE_SERVER)
335 continue;
336
337 if (ctxt.iface->dhcpv6 == MODE_SERVER &&
338 ctxt.iface->ia_assignments.next) {
339 list_for_each_entry(ctxt.c, &ctxt.iface->ia_assignments, head) {
340 if (!(ctxt.c->flags & OAF_BOUND) || ctxt.c->managed_size < 0)
341 continue;
342
343 char duidbuf[264];
344
345 odhcpd_hexlify(duidbuf, ctxt.c->clid_data, ctxt.c->clid_len);
346
347 /* iface DUID iaid hostname lifetime assigned length [addrs...] */
348 ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s %x %s%s %ld %x %u ",
349 ctxt.iface->ifname, duidbuf, ntohl(ctxt.c->iaid),
350 (ctxt.c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
351 (ctxt.c->hostname ? ctxt.c->hostname : "-"),
352 (ctxt.c->valid_until > now ?
353 (ctxt.c->valid_until - now + wall_time) :
354 (INFINITE_VALID(ctxt.c->valid_until) ? -1 : 0)),
355 ctxt.c->assigned, (unsigned)ctxt.c->length);
356
357 if (INFINITE_VALID(ctxt.c->valid_until) || ctxt.c->valid_until > now)
358 dhcpv6_ia_enum_addrs(ctxt.iface, ctxt.c, now,
359 dhcpv6_write_ia_addr, &ctxt);
360
361 ctxt.buf[ctxt.buf_idx - 1] = '\n';
362 fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
363 }
364 }
365
366 if (ctxt.iface->dhcpv4 == MODE_SERVER &&
367 ctxt.iface->dhcpv4_assignments.next) {
368 struct dhcp_assignment *c;
369 list_for_each_entry(c, &ctxt.iface->dhcpv4_assignments, head) {
370 if (!(c->flags & OAF_BOUND))
371 continue;
372
373 char ipbuf[INET6_ADDRSTRLEN];
374 char duidbuf[16];
375 odhcpd_hexlify(duidbuf, c->hwaddr, sizeof(c->hwaddr));
376
377 /* iface DUID iaid hostname lifetime assigned length [addrs...] */
378 ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s ipv4 %s%s %ld %x 32 ",
379 ctxt.iface->ifname, duidbuf,
380 (c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
381 (c->hostname ? c->hostname : "-"),
382 (c->valid_until > now ?
383 (c->valid_until - now + wall_time) :
384 (INFINITE_VALID(c->valid_until) ? -1 : 0)),
385 ntohl(c->addr));
386
387 struct in_addr addr = {.s_addr = c->addr};
388 inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf) - 1);
389
390 if (c->hostname && !(c->flags & OAF_BROKEN_HOSTNAME)) {
391 fputs(ipbuf, ctxt.fp);
392
393 char b[256];
394 if (dn_expand(ctxt.iface->search,
395 ctxt.iface->search + ctxt.iface->search_len,
396 ctxt.iface->search, b, sizeof(b)) > 0)
397 fprintf(ctxt.fp, "\t%s.%s", c->hostname, b);
398
399 fprintf(ctxt.fp, "\t%s\n", c->hostname);
400 md5_hash(ipbuf, strlen(ipbuf), &ctxt.md5);
401 md5_hash(c->hostname, strlen(c->hostname), &ctxt.md5);
402 }
403
404 ctxt.buf_idx += snprintf(ctxt.buf + ctxt.buf_idx,
405 ctxt.buf_len - ctxt.buf_idx,
406 "%s/32 ", ipbuf);
407 ctxt.buf[ctxt.buf_idx - 1] = '\n';
408 fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
409 }
410 }
411 }
412
413 fclose(ctxt.fp);
414 }
415
416 uint8_t newmd5[16];
417 md5_end(newmd5, &ctxt.md5);
418
419 if (config.dhcp_cb && memcmp(newmd5, statemd5, sizeof(newmd5))) {
420 memcpy(statemd5, newmd5, sizeof(statemd5));
421 char *argv[2] = {config.dhcp_cb, NULL};
422 if (!vfork()) {
423 execv(argv[0], argv);
424 _exit(128);
425 }
426 }
427 }
428
429 static void __apply_lease(struct interface *iface, struct dhcp_assignment *a,
430 struct odhcpd_ipaddr *addrs, ssize_t addr_len, bool add)
431 {
432 if (a->length > 64)
433 return;
434
435 for (ssize_t i = 0; i < addr_len; ++i) {
436 struct in6_addr prefix = addrs[i].addr.in6;
437 prefix.s6_addr32[1] |= htonl(a->assigned);
438 prefix.s6_addr32[2] = prefix.s6_addr32[3] = 0;
439 netlink_setup_route(&prefix, (a->managed_size) ? addrs[i].prefix : a->length,
440 iface->ifindex, &a->peer.sin6_addr, 1024, add);
441 }
442 }
443
444 static void apply_lease(struct interface *iface, struct dhcp_assignment *a, bool add)
445 {
446 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
447 ssize_t addrlen = (a->managed) ? a->managed_size : (ssize_t)iface->addr6_len;
448
449 __apply_lease(iface, a, addrs, addrlen, add);
450 }
451
452 /* Set border assignment size based on the IPv6 address prefixes */
453 static void set_border_assignment_size(struct interface *iface, struct dhcp_assignment *b)
454 {
455 time_t now = odhcpd_time();
456 int minprefix = -1;
457
458 for (size_t i = 0; i < iface->addr6_len; ++i) {
459 if (iface->addr6[i].preferred > (uint32_t)now &&
460 iface->addr6[i].prefix < 64 &&
461 iface->addr6[i].prefix > minprefix)
462 minprefix = iface->addr6[i].prefix;
463 }
464
465 if (minprefix > 32 && minprefix <= 64)
466 b->assigned = 1U << (64 - minprefix);
467 else
468 b->assigned = 0;
469 }
470
471 /* More data was received from TCP connection */
472 static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
473 {
474 struct ustream_fd *fd = container_of(s, struct ustream_fd, stream);
475 struct dhcp_assignment *c = container_of(fd, struct dhcp_assignment, managed_sock);
476 time_t now = odhcpd_time();
477 bool first = c->managed_size < 0;
478
479 for (;;) {
480 int pending;
481 char *data = ustream_get_read_buf(s, &pending);
482 char *end = memmem(data, pending, "\n\n", 2);
483
484 if (!end)
485 break;
486
487 end += 2;
488 end[-1] = 0;
489
490 c->managed_size = 0;
491 if (c->accept_reconf)
492 c->reconf_cnt = 1;
493
494 char *saveptr;
495 for (char *line = strtok_r(data, "\n", &saveptr); line; line = strtok_r(NULL, "\n", &saveptr)) {
496 c->managed = realloc(c->managed, (c->managed_size + 1) * sizeof(*c->managed));
497 struct odhcpd_ipaddr *n = &c->managed[c->managed_size];
498
499 char *saveptr2, *x = strtok_r(line, "/", &saveptr2);
500 if (!x || inet_pton(AF_INET6, x, &n->addr) < 1)
501 continue;
502
503 x = strtok_r(NULL, ",", &saveptr2);
504 if (sscanf(x, "%hhu", &n->prefix) < 1)
505 continue;
506
507 x = strtok_r(NULL, ",", &saveptr2);
508 if (sscanf(x, "%u", &n->preferred) < 1)
509 continue;
510
511 x = strtok_r(NULL, ",", &saveptr2);
512 if (sscanf(x, "%u", &n->valid) < 1)
513 continue;
514
515 if (n->preferred > n->valid)
516 continue;
517
518 if (UINT32_MAX - now < n->preferred)
519 n->preferred = UINT32_MAX;
520 else
521 n->preferred += now;
522
523 if (UINT32_MAX - now < n->valid)
524 n->valid = UINT32_MAX;
525 else
526 n->valid += now;
527
528 n->dprefix = 0;
529
530 ++c->managed_size;
531 }
532
533 ustream_consume(s, end - data);
534 }
535
536 if (first && c->managed_size == 0)
537 dhcpv6_ia_free_assignment(c);
538 else if (first && !(c->flags & OAF_STATIC))
539 c->valid_until = now + 150;
540 }
541
542
543 /* TCP transmission has ended, either because of success or timeout or other error */
544 static void managed_handle_pd_done(struct ustream *s)
545 {
546 struct ustream_fd *fd = container_of(s, struct ustream_fd, stream);
547 struct dhcp_assignment *c = container_of(fd, struct dhcp_assignment, managed_sock);
548
549 if (!(c->flags & OAF_STATIC))
550 c->valid_until = odhcpd_time() + 15;
551
552 c->managed_size = 0;
553
554 if (c->accept_reconf)
555 c->reconf_cnt = 1;
556 }
557
558 static bool assign_pd(struct interface *iface, struct dhcp_assignment *assign)
559 {
560 struct dhcp_assignment *c;
561
562 if (iface->dhcpv6_pd_manager[0]) {
563 int fd = usock(USOCK_UNIX | USOCK_TCP, iface->dhcpv6_pd_manager, NULL);
564 if (fd >= 0) {
565 struct pollfd pfd = { .fd = fd, .events = POLLIN };
566 char iaidbuf[298];
567
568 odhcpd_hexlify(iaidbuf, assign->clid_data, assign->clid_len);
569
570 assign->managed_sock.stream.notify_read = managed_handle_pd_data;
571 assign->managed_sock.stream.notify_state = managed_handle_pd_done;
572 ustream_fd_init(&assign->managed_sock, fd);
573 ustream_printf(&assign->managed_sock.stream, "%s,%x\n::/%d,0,0\n\n",
574 iaidbuf, assign->iaid, assign->length);
575 ustream_write_pending(&assign->managed_sock.stream);
576 assign->managed_size = -1;
577
578 if (!(assign->flags & OAF_STATIC))
579 assign->valid_until = odhcpd_time() + 15;
580
581 list_add(&assign->head, &iface->ia_assignments);
582
583 /* Wait initial period of up to 250ms for immediate assignment */
584 if (poll(&pfd, 1, 250) < 0) {
585 syslog(LOG_ERR, "poll(): %m");
586 return false;
587 }
588
589 managed_handle_pd_data(&assign->managed_sock.stream, 0);
590
591 if (fcntl(fd, F_GETFL) >= 0 && assign->managed_size > 0)
592 return true;
593 }
594
595 return false;
596 } else if (iface->addr6_len < 1)
597 return false;
598
599 /* Try honoring the hint first */
600 uint32_t current = 1, asize = (1 << (64 - assign->length)) - 1;
601 if (assign->assigned) {
602 list_for_each_entry(c, &iface->ia_assignments, head) {
603 if (c->length == 128 || c->length == 0)
604 continue;
605
606 if (assign->assigned >= current && assign->assigned + asize < c->assigned) {
607 list_add_tail(&assign->head, &c->head);
608
609 if (assign->flags & OAF_BOUND)
610 apply_lease(iface, assign, true);
611
612 return true;
613 }
614
615 if (c->assigned != 0)
616 current = (c->assigned + (1 << (64 - c->length)));
617 }
618 }
619
620 /* Fallback to a variable assignment */
621 current = 1;
622 list_for_each_entry(c, &iface->ia_assignments, head) {
623 if (c->length == 128 || c->length == 0)
624 continue;
625
626 current = (current + asize) & (~asize);
627 if (current + asize < c->assigned) {
628 assign->assigned = current;
629 list_add_tail(&assign->head, &c->head);
630
631 if (assign->flags & OAF_BOUND)
632 apply_lease(iface, assign, true);
633
634 return true;
635 }
636
637 if (c->assigned != 0)
638 current = (c->assigned + (1 << (64 - c->length)));
639 }
640
641 return false;
642 }
643
644 static bool assign_na(struct interface *iface, struct dhcp_assignment *a)
645 {
646 struct dhcp_assignment *c;
647 uint32_t seed = 0;
648
649 /* Preconfigured assignment by static lease */
650 if (a->assigned) {
651 list_for_each_entry(c, &iface->ia_assignments, head) {
652 if (c->length == 0)
653 continue;
654
655 if (c->assigned > a->assigned || c->length != 128) {
656 list_add_tail(&a->head, &c->head);
657 return true;
658 } else if (c->assigned == a->assigned)
659 return false;
660 }
661 }
662
663 /* Seed RNG with checksum of DUID */
664 for (size_t i = 0; i < a->clid_len; ++i)
665 seed += a->clid_data[i];
666 srand(seed);
667
668 /* Try to assign up to 100x */
669 for (size_t i = 0; i < 100; ++i) {
670 uint32_t try;
671 do try = ((uint32_t)rand()) % 0x0fff; while (try < 0x100);
672
673 if (config_find_lease_by_hostid(try))
674 continue;
675
676 list_for_each_entry(c, &iface->ia_assignments, head) {
677 if (c->length == 0)
678 continue;
679
680 if (c->assigned > try || c->length != 128) {
681 a->assigned = try;
682 list_add_tail(&a->head, &c->head);
683 return true;
684 } else if (c->assigned == try)
685 break;
686 }
687 }
688
689 return false;
690 }
691
692 static void handle_addrlist_change(struct netevent_handler_info *info)
693 {
694 struct interface *iface = info->iface;
695 struct dhcp_assignment *c, *d, *border = list_last_entry(
696 &iface->ia_assignments, struct dhcp_assignment, head);
697 struct list_head reassign = LIST_HEAD_INIT(reassign);
698 time_t now = odhcpd_time();
699
700 list_for_each_entry(c, &iface->ia_assignments, head) {
701 if (c != border && iface->ra_managed == RA_MANAGED_NO_MFLAG
702 && (c->flags & OAF_BOUND))
703 __apply_lease(iface, c, info->addrs_old.addrs,
704 info->addrs_old.len, false);
705 }
706
707 set_border_assignment_size(iface, border);
708
709 list_for_each_entry_safe(c, d, &iface->ia_assignments, head) {
710 if (c->clid_len == 0 || (!INFINITE_VALID(c->valid_until) && c->valid_until < now) ||
711 c->managed_size)
712 continue;
713
714 if (c->length < 128 && c->assigned >= border->assigned && c != border)
715 list_move(&c->head, &reassign);
716 else if (c != border && (c->flags & OAF_BOUND))
717 apply_lease(iface, c, true);
718
719 if (c->accept_reconf && c->reconf_cnt == 0) {
720 struct dhcp_assignment *a;
721
722 start_reconf(c);
723
724 /* Leave all other assignments of that client alone */
725 list_for_each_entry(a, &iface->ia_assignments, head)
726 if (a != c && a->clid_len == c->clid_len &&
727 !memcmp(a->clid_data, c->clid_data, a->clid_len))
728 a->reconf_cnt = INT_MAX;
729 }
730 }
731
732 while (!list_empty(&reassign)) {
733 c = list_first_entry(&reassign, struct dhcp_assignment, head);
734 list_del(&c->head);
735 if (!assign_pd(iface, c)) {
736 c->assigned = 0;
737 list_add(&c->head, &iface->ia_assignments);
738 }
739 }
740
741 dhcpv6_ia_write_statefile();
742 }
743
744 static void reconf_timeout_cb(struct uloop_timeout *event)
745 {
746 struct dhcp_assignment *a = container_of(event, struct dhcp_assignment, reconf_timer);
747
748 if (a->reconf_cnt > 0 && a->reconf_cnt < DHCPV6_REC_MAX_RC) {
749 send_reconf(a);
750 uloop_timeout_set(&a->reconf_timer,
751 DHCPV6_REC_TIMEOUT << a->reconf_cnt);
752 a->reconf_cnt++;
753 } else
754 stop_reconf(a);
755 }
756
757 static void start_reconf(struct dhcp_assignment *a)
758 {
759 uloop_timeout_set(&a->reconf_timer,
760 DHCPV6_REC_TIMEOUT << a->reconf_cnt);
761 a->reconf_timer.cb = reconf_timeout_cb;
762 a->reconf_cnt++;
763
764 send_reconf(a);
765 }
766
767 static void stop_reconf(struct dhcp_assignment *a)
768 {
769 uloop_timeout_cancel(&a->reconf_timer);
770 a->reconf_cnt = 0;
771 a->reconf_timer.cb = NULL;
772 }
773
774 static void valid_until_cb(struct uloop_timeout *event)
775 {
776 struct interface *iface;
777 time_t now = odhcpd_time();
778
779 avl_for_each_element(&interfaces, iface, avl) {
780 struct dhcp_assignment *a, *n;
781
782 if (iface->dhcpv6 != MODE_SERVER || iface->ia_assignments.next == NULL)
783 continue;
784
785 list_for_each_entry_safe(a, n, &iface->ia_assignments, head) {
786 if (!INFINITE_VALID(a->valid_until) && a->valid_until < now) {
787 if ((a->length < 128 && a->clid_len > 0) ||
788 (a->length == 128 && a->clid_len == 0))
789 dhcpv6_ia_free_assignment(a);
790
791 }
792 }
793 }
794 uloop_timeout_set(event, 1000);
795 }
796
797 static size_t build_ia(uint8_t *buf, size_t buflen, uint16_t status,
798 const struct dhcpv6_ia_hdr *ia, struct dhcp_assignment *a,
799 struct interface *iface, bool request)
800 {
801 struct dhcpv6_ia_hdr o_ia = {
802 .type = ia->type,
803 .len = 0,
804 .iaid = ia->iaid,
805 .t1 = 0,
806 .t2 = 0,
807 };
808 size_t ia_len = sizeof(o_ia);
809 time_t now = odhcpd_time();
810
811 if (buflen < ia_len)
812 return 0;
813
814 if (status) {
815 struct __attribute__((packed)) {
816 uint16_t type;
817 uint16_t len;
818 uint16_t val;
819 } o_status = {
820 .type = htons(DHCPV6_OPT_STATUS),
821 .len = htons(sizeof(o_status) - 4),
822 .val = htons(status),
823 };
824
825 memcpy(buf + ia_len, &o_status, sizeof(o_status));
826 ia_len += sizeof(o_status);
827
828 o_ia.len = htons(ia_len - 4);
829 memcpy(buf, &o_ia, sizeof(o_ia));
830
831 return ia_len;
832 }
833
834 if (a) {
835 uint32_t leasetime;
836
837 if (a->leasetime)
838 leasetime = a->leasetime;
839 else
840 leasetime = iface->dhcpv4_leasetime;
841
842 uint32_t pref = leasetime;
843 uint32_t valid = leasetime;
844
845 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
846 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->addr6_len;
847 size_t m = get_preferred_addr(addrs, addrlen);
848
849 for (size_t i = 0; i < addrlen; ++i) {
850 uint32_t prefix_pref = addrs[i].preferred;
851 uint32_t prefix_valid = addrs[i].valid;
852
853 if (!valid_addr(&addrs[i], now))
854 continue;
855
856 if (prefix_pref != UINT32_MAX)
857 prefix_pref -= now;
858
859 if (prefix_valid != UINT32_MAX)
860 prefix_valid -= now;
861
862 if (a->length < 128) {
863 struct dhcpv6_ia_prefix o_ia_p = {
864 .type = htons(DHCPV6_OPT_IA_PREFIX),
865 .len = htons(sizeof(o_ia_p) - 4),
866 .preferred = htonl(prefix_pref),
867 .valid = htonl(prefix_valid),
868 .prefix = (a->managed_size) ? addrs[i].prefix : a->length,
869 .addr = addrs[i].addr.in6,
870 };
871
872 o_ia_p.addr.s6_addr32[1] |= htonl(a->assigned);
873 o_ia_p.addr.s6_addr32[2] = o_ia_p.addr.s6_addr32[3] = 0;
874
875 if ((a->assigned == 0 && a->managed_size == 0) ||
876 !valid_prefix_length(a, addrs[i].prefix))
877 continue;
878
879 if (buflen < ia_len + sizeof(o_ia_p))
880 return 0;
881
882 memcpy(buf + ia_len, &o_ia_p, sizeof(o_ia_p));
883 ia_len += sizeof(o_ia_p);
884 } else {
885 struct dhcpv6_ia_addr o_ia_a = {
886 .type = htons(DHCPV6_OPT_IA_ADDR),
887 .len = htons(sizeof(o_ia_a) - 4),
888 .addr = addrs[i].addr.in6,
889 .preferred = htonl(prefix_pref),
890 .valid = htonl(prefix_valid)
891 };
892
893 o_ia_a.addr.s6_addr32[3] = htonl(a->assigned);
894
895 if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) ||
896 a->assigned == 0)
897 continue;
898
899 if (buflen < ia_len + sizeof(o_ia_a))
900 return 0;
901
902 memcpy(buf + ia_len, &o_ia_a, sizeof(o_ia_a));
903 ia_len += sizeof(o_ia_a);
904 }
905
906 /* Calculate T1 / T2 based on non-deprecated addresses */
907 if (prefix_pref > 0) {
908 if (prefix_pref < pref)
909 pref = prefix_pref;
910
911 if (prefix_valid < valid)
912 valid = prefix_valid;
913 }
914 }
915
916 if (!INFINITE_VALID(a->valid_until))
917 /* UINT32_MAX is considered as infinite leasetime */
918 a->valid_until = (valid == UINT32_MAX) ? 0 : valid + now;
919
920 o_ia.t1 = htonl((pref == UINT32_MAX) ? pref : pref * 5 / 10);
921 o_ia.t2 = htonl((pref == UINT32_MAX) ? pref : pref * 8 / 10);
922
923 if (!o_ia.t1)
924 o_ia.t1 = htonl(1);
925
926 if (!o_ia.t2)
927 o_ia.t2 = htonl(1);
928 }
929
930 if (!request) {
931 uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
932 uint16_t otype, olen;
933
934 dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
935 struct dhcpv6_ia_prefix *ia_p = (struct dhcpv6_ia_prefix *)&odata[-4];
936 struct dhcpv6_ia_addr *ia_a = (struct dhcpv6_ia_addr *)&odata[-4];
937 bool found = false;
938
939 if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*ia_p) - 4) &&
940 (otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*ia_a) - 4))
941 continue;
942
943 if (a) {
944 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
945 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->addr6_len;
946
947 for (size_t i = 0; i < addrlen; ++i) {
948 if (!valid_addr(&addrs[i], now))
949 continue;
950
951 struct in6_addr addr = addrs[i].addr.in6;
952 if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
953 addr.s6_addr32[1] |= htonl(a->assigned);
954 addr.s6_addr32[2] = addr.s6_addr32[3] = 0;
955
956 if (!memcmp(&ia_p->addr, &addr, sizeof(addr)) &&
957 ia_p->prefix == ((a->managed) ? addrs[i].prefix : a->length))
958 found = true;
959 } else {
960 addr.s6_addr32[3] = htonl(a->assigned);
961
962 if (!memcmp(&ia_a->addr, &addr, sizeof(addr)))
963 found = true;
964 }
965 }
966 }
967
968 if (!found) {
969 if (otype == DHCPV6_OPT_IA_PREFIX) {
970 struct dhcpv6_ia_prefix o_ia_p = {
971 .type = htons(DHCPV6_OPT_IA_PREFIX),
972 .len = htons(sizeof(o_ia_p) - 4),
973 .preferred = 0,
974 .valid = 0,
975 .prefix = ia_p->prefix,
976 .addr = ia_p->addr,
977 };
978
979 if (buflen < ia_len + sizeof(o_ia_p))
980 return 0;
981
982 memcpy(buf + ia_len, &o_ia_p, sizeof(o_ia_p));
983 ia_len += sizeof(o_ia_p);
984 } else {
985 struct dhcpv6_ia_addr o_ia_a = {
986 .type = htons(DHCPV6_OPT_IA_ADDR),
987 .len = htons(sizeof(o_ia_a) - 4),
988 .addr = ia_a->addr,
989 .preferred = 0,
990 .valid = 0,
991 };
992
993 if (buflen < ia_len + sizeof(o_ia_a))
994 continue;
995
996 memcpy(buf + ia_len, &o_ia_a, sizeof(o_ia_a));
997 ia_len += sizeof(o_ia_a);
998 }
999 }
1000 }
1001 }
1002
1003 o_ia.len = htons(ia_len - 4);
1004 memcpy(buf, &o_ia, sizeof(o_ia));
1005 return ia_len;
1006 }
1007
1008 struct log_ctxt {
1009 char *buf;
1010 int buf_len;
1011 int buf_idx;
1012 };
1013
1014 static void dhcpv6_log_ia_addr(struct in6_addr *addr, int prefix, _unused uint32_t pref,
1015 _unused uint32_t valid, void *arg)
1016 {
1017 struct log_ctxt *ctxt = (struct log_ctxt *)arg;
1018 char addrbuf[INET6_ADDRSTRLEN];
1019
1020 inet_ntop(AF_INET6, addr, addrbuf, sizeof(addrbuf));
1021 ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx, ctxt->buf_len - ctxt->buf_idx,
1022 "%s/%d ", addrbuf, prefix);
1023 }
1024
1025 static void dhcpv6_log(uint8_t msgtype, struct interface *iface, time_t now,
1026 const char *duidbuf, bool is_pd, struct dhcp_assignment *a, int code)
1027 {
1028 const char *type = "UNKNOWN";
1029 const char *status = "UNKNOWN";
1030
1031 switch (msgtype) {
1032 case DHCPV6_MSG_SOLICIT:
1033 type = "SOLICIT";
1034 break;
1035 case DHCPV6_MSG_REQUEST:
1036 type = "REQUEST";
1037 break;
1038 case DHCPV6_MSG_CONFIRM:
1039 type = "CONFIRM";
1040 break;
1041 case DHCPV6_MSG_RENEW:
1042 type = "RENEW";
1043 break;
1044 case DHCPV6_MSG_REBIND:
1045 type = "REBIND";
1046 break;
1047 case DHCPV6_MSG_RELEASE:
1048 type = "RELEASE";
1049 break;
1050 case DHCPV6_MSG_DECLINE:
1051 type = "DECLINE";
1052 break;
1053 }
1054
1055 switch (code) {
1056 case DHCPV6_STATUS_OK:
1057 status = "ok";
1058 break;
1059 case DHCPV6_STATUS_NOADDRSAVAIL:
1060 status = "no addresses available";
1061 break;
1062 case DHCPV6_STATUS_NOBINDING:
1063 status = "no binding";
1064 break;
1065 case DHCPV6_STATUS_NOTONLINK:
1066 status = "not on-link";
1067 break;
1068 case DHCPV6_STATUS_NOPREFIXAVAIL:
1069 status = "no prefix available";
1070 break;
1071 }
1072
1073 char leasebuf[256] = "";
1074
1075 if (a) {
1076 struct log_ctxt ctxt = {.buf = leasebuf,
1077 .buf_len = sizeof(leasebuf),
1078 .buf_idx = 0 };
1079
1080 dhcpv6_ia_enum_addrs(iface, a, now, dhcpv6_log_ia_addr, &ctxt);
1081 }
1082
1083 syslog(LOG_WARNING, "DHCPV6 %s %s from %s on %s: %s %s", type, (is_pd) ? "IA_PD" : "IA_NA",
1084 duidbuf, iface->name, status, leasebuf);
1085 }
1086
1087 static bool dhcpv6_ia_on_link(const struct dhcpv6_ia_hdr *ia, struct dhcp_assignment *a,
1088 struct interface *iface)
1089 {
1090 struct odhcpd_ipaddr *addrs = (a && a->managed) ? a->managed : iface->addr6;
1091 size_t addrlen = (a && a->managed) ? (size_t)a->managed_size : iface->addr6_len;
1092 time_t now = odhcpd_time();
1093 uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
1094 uint16_t otype, olen;
1095 bool onlink = true;
1096
1097 dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
1098 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix *)&odata[-4];
1099 struct dhcpv6_ia_addr *n = (struct dhcpv6_ia_addr *)&odata[-4];
1100
1101 if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*p) - 4) &&
1102 (otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*n) - 4))
1103 continue;
1104
1105 onlink = false;
1106 for (size_t i = 0; i < addrlen; ++i) {
1107 if (!valid_addr(&addrs[i], now))
1108 continue;
1109
1110 if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
1111 if (p->prefix < addrs[i].prefix ||
1112 odhcpd_bmemcmp(&p->addr, &addrs[i].addr.in6, addrs[i].prefix))
1113 continue;
1114
1115 } else if (odhcpd_bmemcmp(&n->addr, &addrs[i].addr.in6, addrs[i].prefix))
1116 continue;
1117
1118 onlink = true;
1119 }
1120
1121 if (!onlink)
1122 break;
1123 }
1124
1125 return onlink;
1126 }
1127
1128 ssize_t dhcpv6_ia_handle_IAs(uint8_t *buf, size_t buflen, struct interface *iface,
1129 const struct sockaddr_in6 *addr, const void *data, const uint8_t *end)
1130 {
1131 struct lease *l;
1132 struct dhcp_assignment *first = NULL;
1133 const struct dhcpv6_client_header *hdr = data;
1134 time_t now = odhcpd_time();
1135 uint16_t otype, olen, clid_len = 0;
1136 uint8_t *start = (uint8_t *)&hdr[1], *odata;
1137 uint8_t *clid_data = NULL, mac[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
1138 size_t hostname_len = 0, response_len = 0;
1139 bool notonlink = false, rapid_commit = false, accept_reconf = false;
1140 char duidbuf[261], hostname[256];
1141
1142 dhcpv6_for_each_option(start, end, otype, olen, odata) {
1143 if (otype == DHCPV6_OPT_CLIENTID) {
1144 clid_data = odata;
1145 clid_len = olen;
1146
1147 if (olen == 14 && odata[0] == 0 && odata[1] == 1)
1148 memcpy(mac, &odata[8], sizeof(mac));
1149 else if (olen == 10 && odata[0] == 0 && odata[1] == 3)
1150 memcpy(mac, &odata[4], sizeof(mac));
1151
1152 if (olen <= 130)
1153 odhcpd_hexlify(duidbuf, odata, olen);
1154 } else if (otype == DHCPV6_OPT_FQDN && olen >= 2 && olen <= 255) {
1155 uint8_t fqdn_buf[256];
1156 memcpy(fqdn_buf, odata, olen);
1157 fqdn_buf[olen++] = 0;
1158
1159 if (dn_expand(&fqdn_buf[1], &fqdn_buf[olen], &fqdn_buf[1], hostname, sizeof(hostname)) > 0)
1160 hostname_len = strcspn(hostname, ".");
1161 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT)
1162 accept_reconf = true;
1163 else if (otype == DHCPV6_OPT_RAPID_COMMIT && hdr->msg_type == DHCPV6_MSG_SOLICIT)
1164 rapid_commit = true;
1165 }
1166
1167 if (!clid_data || !clid_len || clid_len > 130)
1168 goto out;
1169
1170 l = config_find_lease_by_duid(clid_data, clid_len);
1171 if (!l)
1172 l = config_find_lease_by_mac(mac);
1173
1174 dhcpv6_for_each_option(start, end, otype, olen, odata) {
1175 bool is_pd = (otype == DHCPV6_OPT_IA_PD);
1176 bool is_na = (otype == DHCPV6_OPT_IA_NA);
1177 bool ia_addr_present = false;
1178 if (!is_pd && !is_na)
1179 continue;
1180
1181 struct dhcpv6_ia_hdr *ia = (struct dhcpv6_ia_hdr*)&odata[-4];
1182 size_t ia_response_len = 0;
1183 uint8_t reqlen = (is_pd) ? 62 : 128;
1184 uint32_t reqhint = 0;
1185
1186 /* Parse request hint for IA-PD */
1187 if (is_pd) {
1188 uint8_t *sdata;
1189 uint16_t stype, slen;
1190 dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1191 if (stype != DHCPV6_OPT_IA_PREFIX || slen < sizeof(struct dhcpv6_ia_prefix) - 4)
1192 continue;
1193
1194 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&sdata[-4];
1195 if (p->prefix) {
1196 reqlen = p->prefix;
1197 reqhint = ntohl(p->addr.s6_addr32[1]);
1198 if (reqlen > 32 && reqlen <= 64)
1199 reqhint &= (1U << (64 - reqlen)) - 1;
1200 }
1201 }
1202
1203 if (reqlen > 64)
1204 reqlen = 64;
1205 } else if (is_na) {
1206 uint8_t *sdata;
1207 uint16_t stype, slen;
1208 dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1209 if (stype != DHCPV6_OPT_IA_ADDR || slen < sizeof(struct dhcpv6_ia_addr) - 4)
1210 continue;
1211
1212 ia_addr_present = true;
1213 }
1214 }
1215
1216 /* Find assignment */
1217 struct dhcp_assignment *c, *a = NULL;
1218 list_for_each_entry(c, &iface->ia_assignments, head) {
1219 if ((c->clid_len == clid_len && !memcmp(c->clid_data, clid_data, clid_len)) &&
1220 c->iaid == ia->iaid && (INFINITE_VALID(c->valid_until) || now < c->valid_until) &&
1221 ((is_pd && c->length <= 64) || (is_na && c->length == 128))) {
1222 a = c;
1223
1224 /* Reset state */
1225 if (a->flags & OAF_BOUND)
1226 apply_lease(iface, a, false);
1227
1228 stop_reconf(a);
1229 break;
1230 }
1231 }
1232
1233 if (l && a && a->lease != l) {
1234 dhcpv6_ia_free_assignment(a);
1235 a = NULL;
1236 }
1237
1238 /* Generic message handling */
1239 uint16_t status = DHCPV6_STATUS_OK;
1240 if (a && a->managed_size < 0)
1241 return -1;
1242
1243 if (hdr->msg_type == DHCPV6_MSG_SOLICIT ||
1244 hdr->msg_type == DHCPV6_MSG_REQUEST ||
1245 (hdr->msg_type == DHCPV6_MSG_REBIND && !a)) {
1246 bool assigned = !!a;
1247
1248 if (!a) {
1249 if ((!iface->no_dynamic_dhcp || (l && is_na)) &&
1250 (iface->dhcpv6_pd || iface->dhcpv6_na)) {
1251 /* Create new binding */
1252 a = calloc(1, sizeof(*a) + clid_len);
1253
1254 if (a) {
1255 a->clid_len = clid_len;
1256 memcpy(a->clid_data, clid_data, clid_len);
1257 a->iaid = ia->iaid;
1258 a->length = reqlen;
1259 a->peer = *addr;
1260 a->assigned = is_na && l ? l->hostid : reqhint;
1261 /* Set valid time to 0 for static lease indicating */
1262 /* infinite lifetime otherwise current time */
1263 a->valid_until = l ? 0 : now;
1264 a->iface = iface;
1265 a->flags = OAF_DHCPV6;
1266
1267 if (first)
1268 memcpy(a->key, first->key, sizeof(a->key));
1269 else
1270 odhcpd_urandom(a->key, sizeof(a->key));
1271
1272 if (is_pd && iface->dhcpv6_pd)
1273 while (!(assigned = assign_pd(iface, a)) &&
1274 !a->managed_size && ++a->length <= 64);
1275 else if (is_na && iface->dhcpv6_na)
1276 assigned = assign_na(iface, a);
1277
1278 if (l && assigned) {
1279 a->flags |= OAF_STATIC;
1280
1281 if (l->hostname)
1282 a->hostname = strdup(l->hostname);
1283
1284 if (l->leasetime)
1285 a->leasetime = l->leasetime;
1286
1287 list_add(&a->lease_list, &l->assignments);
1288 a->lease = l;
1289 }
1290
1291 if (a->managed_size && !assigned)
1292 return -1;
1293 }
1294 }
1295 }
1296
1297 if (!assigned || iface->addr6_len == 0)
1298 /* Set error status */
1299 status = (is_pd) ? DHCPV6_STATUS_NOPREFIXAVAIL : DHCPV6_STATUS_NOADDRSAVAIL;
1300 else if (hdr->msg_type == DHCPV6_MSG_REQUEST && !dhcpv6_ia_on_link(ia, a, iface)) {
1301 /* Send NOTONLINK staus for the IA */
1302 status = DHCPV6_STATUS_NOTONLINK;
1303 assigned = false;
1304 } else if (accept_reconf && assigned && !first &&
1305 hdr->msg_type != DHCPV6_MSG_REBIND) {
1306 size_t handshake_len = 4;
1307 buf[0] = 0;
1308 buf[1] = DHCPV6_OPT_RECONF_ACCEPT;
1309 buf[2] = 0;
1310 buf[3] = 0;
1311
1312 if (hdr->msg_type == DHCPV6_MSG_REQUEST) {
1313 struct dhcpv6_auth_reconfigure auth = {
1314 htons(DHCPV6_OPT_AUTH),
1315 htons(sizeof(auth) - 4),
1316 3, 1, 0,
1317 {htonl(time(NULL)), htonl(++serial)},
1318 1,
1319 {0}
1320 };
1321 memcpy(auth.key, a->key, sizeof(a->key));
1322 memcpy(buf + handshake_len, &auth, sizeof(auth));
1323 handshake_len += sizeof(auth);
1324 }
1325
1326
1327 buf += handshake_len;
1328 buflen -= handshake_len;
1329 response_len += handshake_len;
1330
1331 first = a;
1332 }
1333
1334 ia_response_len = build_ia(buf, buflen, status, ia, a, iface,
1335 hdr->msg_type == DHCPV6_MSG_REBIND ? false : true);
1336
1337 /* Was only a solicitation: mark binding for removal */
1338 if (assigned && hdr->msg_type == DHCPV6_MSG_SOLICIT && !rapid_commit) {
1339 a->flags &= ~OAF_BOUND;
1340 a->flags |= OAF_TENTATIVE;
1341
1342 if (!(a->flags & OAF_STATIC))
1343 /* Keep tentative assignment around for 60 seconds */
1344 a->valid_until = now + 60;
1345
1346 } else if (assigned &&
1347 ((hdr->msg_type == DHCPV6_MSG_SOLICIT && rapid_commit) ||
1348 hdr->msg_type == DHCPV6_MSG_REQUEST ||
1349 hdr->msg_type == DHCPV6_MSG_REBIND)) {
1350 if ((!(a->flags & OAF_STATIC) || !a->hostname) && hostname_len > 0) {
1351 a->hostname = realloc(a->hostname, hostname_len + 1);
1352 if (a->hostname) {
1353 memcpy(a->hostname, hostname, hostname_len);
1354 a->hostname[hostname_len] = 0;
1355
1356 if (odhcpd_valid_hostname(a->hostname))
1357 a->flags &= ~OAF_BROKEN_HOSTNAME;
1358 else
1359 a->flags |= OAF_BROKEN_HOSTNAME;
1360 }
1361 }
1362 a->accept_reconf = accept_reconf;
1363 a->flags &= ~OAF_TENTATIVE;
1364 a->flags |= OAF_BOUND;
1365 apply_lease(iface, a, true);
1366 } else if (!assigned && a && a->managed_size == 0) {
1367 /* Cleanup failed assignment */
1368 dhcpv6_ia_free_assignment(a);
1369 a = NULL;
1370 }
1371 } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1372 hdr->msg_type == DHCPV6_MSG_RELEASE ||
1373 hdr->msg_type == DHCPV6_MSG_REBIND ||
1374 hdr->msg_type == DHCPV6_MSG_DECLINE) {
1375 if (!a && hdr->msg_type != DHCPV6_MSG_REBIND) {
1376 status = DHCPV6_STATUS_NOBINDING;
1377 ia_response_len = build_ia(buf, buflen, status, ia, a, iface, false);
1378 } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1379 hdr->msg_type == DHCPV6_MSG_REBIND) {
1380 ia_response_len = build_ia(buf, buflen, status, ia, a, iface, false);
1381 if (a) {
1382 a->flags |= OAF_BOUND;
1383 apply_lease(iface, a, true);
1384 }
1385 } else if (hdr->msg_type == DHCPV6_MSG_RELEASE) {
1386 if (!(a->flags & OAF_STATIC))
1387 a->valid_until = now - 1;
1388
1389 if (a->flags & OAF_BOUND) {
1390 apply_lease(iface, a, false);
1391 a->flags &= ~OAF_BOUND;
1392 }
1393 } else if (hdr->msg_type == DHCPV6_MSG_DECLINE && a->length == 128) {
1394 a->flags &= ~OAF_BOUND;
1395
1396 if (!(a->flags & OAF_STATIC)) {
1397 a->clid_len = 0;
1398 a->valid_until = now + 3600; /* Block address for 1h */
1399 }
1400 }
1401 } else if (hdr->msg_type == DHCPV6_MSG_CONFIRM) {
1402 if (ia_addr_present && !dhcpv6_ia_on_link(ia, a, iface)) {
1403 notonlink = true;
1404 break;
1405 }
1406
1407 if (!ia_addr_present || !a || !(a->flags & OAF_BOUND)) {
1408 response_len = 0;
1409 goto out;
1410 }
1411 }
1412
1413 buf += ia_response_len;
1414 buflen -= ia_response_len;
1415 response_len += ia_response_len;
1416 dhcpv6_log(hdr->msg_type, iface, now, duidbuf, is_pd, a, status);
1417 }
1418
1419 switch (hdr->msg_type) {
1420 case DHCPV6_MSG_RELEASE:
1421 case DHCPV6_MSG_DECLINE:
1422 case DHCPV6_MSG_CONFIRM:
1423 if (response_len + 6 < buflen) {
1424 buf[0] = 0;
1425 buf[1] = DHCPV6_OPT_STATUS;
1426 buf[2] = 0;
1427 buf[3] = 2;
1428 buf[4] = 0;
1429 buf[5] = (notonlink) ? DHCPV6_STATUS_NOTONLINK : DHCPV6_STATUS_OK;
1430 response_len += 6;
1431 }
1432 break;
1433
1434 default:
1435 break;
1436 }
1437
1438 dhcpv6_ia_write_statefile();
1439
1440 out:
1441 return response_len;
1442 }
OpenWrt DHCP Server