projects / project / odhcpd.git / blob
? search:


2820946f2dfdaf2439162556877f2d01eb798290
[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 free_dhcpv6_assignment(struct dhcp_assignment *c);
44 static void set_border_assignment_size(struct interface *iface, struct dhcp_assignment *b);
45 static void handle_addrlist_change(struct netevent_handler_info *info);
46 static void start_reconf(struct dhcp_assignment *a);
47 static void stop_reconf(struct dhcp_assignment *a);
48 static void valid_until_cb(struct uloop_timeout *event);
49
50 static struct netevent_handler dhcpv6_netevent_handler = { .cb = dhcpv6_netevent_cb, };
51 static struct uloop_timeout valid_until_timeout = {.cb = valid_until_cb};
52 static uint32_t serial = 0;
53 static uint8_t statemd5[16];
54
55 int dhcpv6_ia_init(void)
56 {
57 uloop_timeout_set(&valid_until_timeout, 1000);
58
59 netlink_add_netevent_handler(&dhcpv6_netevent_handler);
60
61 return 0;
62 }
63
64 int dhcpv6_ia_setup_interface(struct interface *iface, bool enable)
65 {
66 if (!enable && iface->ia_assignments.next) {
67 struct dhcp_assignment *c;
68
69 while (!list_empty(&iface->ia_assignments)) {
70 c = list_first_entry(&iface->ia_assignments, struct dhcp_assignment, head);
71 free_dhcpv6_assignment(c);
72 }
73 }
74
75 if (enable && iface->dhcpv6 == MODE_SERVER) {
76 struct dhcp_assignment *border;
77 struct lease *lease;
78
79 if (!iface->ia_assignments.next)
80 INIT_LIST_HEAD(&iface->ia_assignments);
81
82 if (list_empty(&iface->ia_assignments)) {
83 border = calloc(1, sizeof(*border));
84
85 if (!border) {
86 syslog(LOG_ERR, "Calloc failed for border on %s", iface->name);
87 return -1;
88 }
89
90 border->length = 64;
91 list_add(&border->head, &iface->ia_assignments);
92 } else
93 border = list_last_entry(&iface->ia_assignments, struct dhcp_assignment, head);
94
95 set_border_assignment_size(iface, border);
96
97 /* Parse static entries */
98 list_for_each_entry(lease, &leases, head) {
99 /* Construct entry */
100 size_t duid_len = lease->duid_len ? lease->duid_len : 14;
101 struct dhcp_assignment *a = calloc(1, sizeof(*a) + duid_len);
102 if (!a) {
103 syslog(LOG_ERR, "Calloc failed for static lease assignment on %s",
104 iface->name);
105 return -1;
106 }
107
108 a->leasetime = lease->dhcpv4_leasetime;
109
110 a->clid_len = duid_len;
111 a->length = 128;
112 if (lease->hostid) {
113 a->assigned = lease->hostid;
114 } else {
115 uint32_t i4a = ntohl(lease->ipaddr.s_addr) & 0xff;
116 a->assigned = ((i4a / 100) << 8) | (((i4a % 100) / 10) << 4) | (i4a % 10);
117 }
118
119 odhcpd_urandom(a->key, sizeof(a->key));
120 memcpy(a->clid_data, lease->duid, lease->duid_len);
121 memcpy(a->mac, lease->mac.ether_addr_octet, sizeof(a->mac));
122 /* Static assignment */
123 a->flags |= OAF_STATIC;
124 /* Infinite valid */
125 a->valid_until = 0;
126
127 /* Assign to all interfaces */
128 struct dhcp_assignment *c;
129 list_for_each_entry(c, &iface->ia_assignments, head) {
130 if (c->length != 128 || c->assigned > a->assigned) {
131 list_add_tail(&a->head, &c->head);
132 break;
133 } else if (c->assigned == a->assigned)
134 /* Already an assignment with that number */
135 break;
136 }
137
138 if (a->head.next) {
139 a->iface = iface;
140 if (lease->hostname[0]) {
141 free(a->hostname);
142 a->hostname = strdup(lease->hostname);
143 }
144 } else
145 free_dhcpv6_assignment(a);
146 }
147 }
148 return 0;
149 }
150
151
152 static void dhcpv6_netevent_cb(unsigned long event, struct netevent_handler_info *info)
153 {
154 struct interface *iface = info->iface;
155
156 if (!iface || iface->dhcpv6 != MODE_SERVER)
157 return;
158
159 switch (event) {
160 case NETEV_ADDR6LIST_CHANGE:
161 handle_addrlist_change(info);
162 break;
163 default:
164 break;
165 }
166 }
167
168
169 static void free_dhcpv6_assignment(struct dhcp_assignment *c)
170 {
171 if (c->managed_sock.fd.registered) {
172 ustream_free(&c->managed_sock.stream);
173 close(c->managed_sock.fd.fd);
174 }
175
176 if (c->head.next)
177 list_del(&c->head);
178
179 if (c->reconf_cnt)
180 stop_reconf(c);
181
182 free(c->managed);
183 free(c->hostname);
184 free(c);
185 }
186
187 static inline bool valid_prefix_length(const struct dhcp_assignment *a, const uint8_t prefix_length)
188 {
189 return (a->managed_size || a->length > prefix_length);
190 }
191
192 static inline bool valid_addr(const struct odhcpd_ipaddr *addr, time_t now)
193 {
194 return (addr->prefix <= 96 && addr->preferred > (uint32_t)now);
195 }
196
197 static size_t get_preferred_addr(const struct odhcpd_ipaddr *addrs, const size_t addrlen)
198 {
199 size_t i, m;
200
201 for (i = 0, m = 0; i < addrlen; ++i) {
202 if (addrs[i].preferred > addrs[m].preferred ||
203 (addrs[i].preferred == addrs[m].preferred &&
204 memcmp(&addrs[i].addr, &addrs[m].addr, 16) > 0))
205 m = i;
206 }
207
208 return m;
209 }
210
211 static int send_reconf(struct dhcp_assignment *assign)
212 {
213 struct {
214 struct dhcpv6_client_header hdr;
215 uint16_t srvid_type;
216 uint16_t srvid_len;
217 uint16_t duid_type;
218 uint16_t hardware_type;
219 uint8_t mac[6];
220 uint16_t msg_type;
221 uint16_t msg_len;
222 uint8_t msg_id;
223 struct dhcpv6_auth_reconfigure auth;
224 uint16_t clid_type;
225 uint16_t clid_len;
226 uint8_t clid_data[128];
227 } __attribute__((packed)) reconf_msg = {
228 .hdr = {DHCPV6_MSG_RECONFIGURE, {0, 0, 0}},
229 .srvid_type = htons(DHCPV6_OPT_SERVERID),
230 .srvid_len = htons(10),
231 .duid_type = htons(3),
232 .hardware_type = htons(1),
233 .msg_type = htons(DHCPV6_OPT_RECONF_MSG),
234 .msg_len = htons(1),
235 .msg_id = DHCPV6_MSG_RENEW,
236 .auth = {htons(DHCPV6_OPT_AUTH),
237 htons(sizeof(reconf_msg.auth) - 4), 3, 1, 0,
238 {htonl(time(NULL)), htonl(++serial)}, 2, {0}},
239 .clid_type = htons(DHCPV6_OPT_CLIENTID),
240 .clid_len = htons(assign->clid_len),
241 .clid_data = {0},
242 };
243 struct interface *iface = assign->iface;
244
245 odhcpd_get_mac(iface, reconf_msg.mac);
246 memcpy(reconf_msg.clid_data, assign->clid_data, assign->clid_len);
247 struct iovec iov = {&reconf_msg, sizeof(reconf_msg) - 128 + assign->clid_len};
248
249 md5_ctx_t md5;
250 uint8_t secretbytes[64];
251 memset(secretbytes, 0, sizeof(secretbytes));
252 memcpy(secretbytes, assign->key, sizeof(assign->key));
253
254 for (size_t i = 0; i < sizeof(secretbytes); ++i)
255 secretbytes[i] ^= 0x36;
256
257 md5_begin(&md5);
258 md5_hash(secretbytes, sizeof(secretbytes), &md5);
259 md5_hash(iov.iov_base, iov.iov_len, &md5);
260 md5_end(reconf_msg.auth.key, &md5);
261
262 for (size_t i = 0; i < sizeof(secretbytes); ++i) {
263 secretbytes[i] ^= 0x36;
264 secretbytes[i] ^= 0x5c;
265 }
266
267 md5_begin(&md5);
268 md5_hash(secretbytes, sizeof(secretbytes), &md5);
269 md5_hash(reconf_msg.auth.key, 16, &md5);
270 md5_end(reconf_msg.auth.key, &md5);
271
272 return odhcpd_send(iface->dhcpv6_event.uloop.fd, &assign->peer, &iov, 1, iface);
273 }
274
275 void dhcpv6_ia_enum_addrs(struct interface *iface, struct dhcp_assignment *c,
276 time_t now, dhcpv6_binding_cb_handler_t func, void *arg)
277 {
278 struct odhcpd_ipaddr *addrs = (c->managed) ? c->managed : iface->addr6;
279 size_t addrlen = (c->managed) ? (size_t)c->managed_size : iface->addr6_len;
280 size_t m = get_preferred_addr(addrs, addrlen);
281
282 for (size_t i = 0; i < addrlen; ++i) {
283 struct in6_addr addr;
284 uint32_t pref, valid;
285 int prefix = c->managed ? addrs[i].prefix : c->length;
286
287 if (!valid_addr(&addrs[i], now))
288 continue;
289
290 addr = addrs[i].addr.in6;
291 pref = addrs[i].preferred;
292 valid = addrs[i].valid;
293 if (prefix == 128) {
294 if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs))
295 continue;
296
297 addr.s6_addr32[3] = htonl(c->assigned);
298 } else {
299 if (!valid_prefix_length(c, addrs[i].prefix))
300 continue;
301
302 addr.s6_addr32[1] |= htonl(c->assigned);
303 addr.s6_addr32[2] = addr.s6_addr32[3] = 0;
304 }
305
306 if (pref != UINT32_MAX)
307 pref -= now;
308
309 if (valid != UINT32_MAX)
310 valid -= now;
311
312 func(&addr, prefix, pref, valid, arg);
313 }
314 }
315
316 struct write_ctxt {
317 FILE *fp;
318 md5_ctx_t md5;
319 struct dhcp_assignment *c;
320 struct interface *iface;
321 char *buf;
322 int buf_len;
323 int buf_idx;
324 };
325
326 void dhcpv6_write_ia_addr(struct in6_addr *addr, int prefix, _unused uint32_t pref,
327 _unused uint32_t valid, void *arg)
328 {
329 struct write_ctxt *ctxt = (struct write_ctxt *)arg;
330 char ipbuf[INET6_ADDRSTRLEN];
331
332 inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf) - 1);
333
334 if (ctxt->c->length == 128 && ctxt->c->hostname &&
335 !(ctxt->c->flags & OAF_BROKEN_HOSTNAME)) {
336 fputs(ipbuf, ctxt->fp);
337
338 char b[256];
339 if (dn_expand(ctxt->iface->search, ctxt->iface->search + ctxt->iface->search_len,
340 ctxt->iface->search, b, sizeof(b)) > 0)
341 fprintf(ctxt->fp, "\t%s.%s", ctxt->c->hostname, b);
342
343 fprintf(ctxt->fp, "\t%s\n", ctxt->c->hostname);
344 md5_hash(ipbuf, strlen(ipbuf), &ctxt->md5);
345 md5_hash(ctxt->c->hostname, strlen(ctxt->c->hostname), &ctxt->md5);
346 }
347
348 ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx,ctxt->buf_len - ctxt->buf_idx,
349 "%s/%d ", ipbuf, prefix);
350 }
351
352 void dhcpv6_ia_write_statefile(void)
353 {
354 struct write_ctxt ctxt;
355
356 md5_begin(&ctxt.md5);
357
358 if (config.dhcp_statefile) {
359 time_t now = odhcpd_time(), wall_time = time(NULL);
360 int fd = open(config.dhcp_statefile, O_CREAT | O_WRONLY | O_CLOEXEC, 0644);
361 char leasebuf[512];
362
363 if (fd < 0)
364 return;
365 int ret;
366 ret = lockf(fd, F_LOCK, 0);
367 if (ret < 0) {
368 close(fd);
369 return;
370 }
371 if (ftruncate(fd, 0) < 0) {}
372
373 ctxt.fp = fdopen(fd, "w");
374 if (!ctxt.fp) {
375 close(fd);
376 return;
377 }
378
379 ctxt.buf = leasebuf;
380 ctxt.buf_len = sizeof(leasebuf);
381
382 avl_for_each_element(&interfaces, ctxt.iface, avl) {
383 if (ctxt.iface->dhcpv6 != MODE_SERVER &&
384 ctxt.iface->dhcpv4 != MODE_SERVER)
385 continue;
386
387 if (ctxt.iface->dhcpv6 == MODE_SERVER &&
388 ctxt.iface->ia_assignments.next) {
389 list_for_each_entry(ctxt.c, &ctxt.iface->ia_assignments, head) {
390 if (!(ctxt.c->flags & OAF_BOUND) || ctxt.c->managed_size < 0)
391 continue;
392
393 char duidbuf[264];
394
395 odhcpd_hexlify(duidbuf, ctxt.c->clid_data, ctxt.c->clid_len);
396
397 /* iface DUID iaid hostname lifetime assigned length [addrs...] */
398 ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s %x %s%s %ld %x %u ",
399 ctxt.iface->ifname, duidbuf, ntohl(ctxt.c->iaid),
400 (ctxt.c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
401 (ctxt.c->hostname ? ctxt.c->hostname : "-"),
402 (ctxt.c->valid_until > now ?
403 (ctxt.c->valid_until - now + wall_time) :
404 (INFINITE_VALID(ctxt.c->valid_until) ? -1 : 0)),
405 ctxt.c->assigned, (unsigned)ctxt.c->length);
406
407 if (INFINITE_VALID(ctxt.c->valid_until) || ctxt.c->valid_until > now)
408 dhcpv6_ia_enum_addrs(ctxt.iface, ctxt.c, now,
409 dhcpv6_write_ia_addr, &ctxt);
410
411 ctxt.buf[ctxt.buf_idx - 1] = '\n';
412 fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
413 }
414 }
415
416 if (ctxt.iface->dhcpv4 == MODE_SERVER &&
417 ctxt.iface->dhcpv4_assignments.next) {
418 struct dhcp_assignment *c;
419 list_for_each_entry(c, &ctxt.iface->dhcpv4_assignments, head) {
420 if (!(c->flags & OAF_BOUND))
421 continue;
422
423 char ipbuf[INET6_ADDRSTRLEN];
424 char duidbuf[16];
425 odhcpd_hexlify(duidbuf, c->hwaddr, sizeof(c->hwaddr));
426
427 /* iface DUID iaid hostname lifetime assigned length [addrs...] */
428 ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s ipv4 %s%s %ld %x 32 ",
429 ctxt.iface->ifname, duidbuf,
430 (c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
431 (c->hostname ? c->hostname : "-"),
432 (c->valid_until > now ?
433 (c->valid_until - now + wall_time) :
434 (INFINITE_VALID(c->valid_until) ? -1 : 0)),
435 ntohl(c->addr));
436
437 struct in_addr addr = {.s_addr = c->addr};
438 inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf) - 1);
439
440 if (c->hostname && !(c->flags & OAF_BROKEN_HOSTNAME)) {
441 fputs(ipbuf, ctxt.fp);
442
443 char b[256];
444 if (dn_expand(ctxt.iface->search,
445 ctxt.iface->search + ctxt.iface->search_len,
446 ctxt.iface->search, b, sizeof(b)) > 0)
447 fprintf(ctxt.fp, "\t%s.%s", c->hostname, b);
448
449 fprintf(ctxt.fp, "\t%s\n", c->hostname);
450 md5_hash(ipbuf, strlen(ipbuf), &ctxt.md5);
451 md5_hash(c->hostname, strlen(c->hostname), &ctxt.md5);
452 }
453
454 ctxt.buf_idx += snprintf(ctxt.buf + ctxt.buf_idx,
455 ctxt.buf_len - ctxt.buf_idx,
456 "%s/32 ", ipbuf);
457 ctxt.buf[ctxt.buf_idx - 1] = '\n';
458 fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
459 }
460 }
461 }
462
463 fclose(ctxt.fp);
464 }
465
466 uint8_t newmd5[16];
467 md5_end(newmd5, &ctxt.md5);
468
469 if (config.dhcp_cb && memcmp(newmd5, statemd5, sizeof(newmd5))) {
470 memcpy(statemd5, newmd5, sizeof(statemd5));
471 char *argv[2] = {config.dhcp_cb, NULL};
472 if (!vfork()) {
473 execv(argv[0], argv);
474 _exit(128);
475 }
476 }
477 }
478
479 static void __apply_lease(struct interface *iface, struct dhcp_assignment *a,
480 struct odhcpd_ipaddr *addrs, ssize_t addr_len, bool add)
481 {
482 if (a->length > 64)
483 return;
484
485 for (ssize_t i = 0; i < addr_len; ++i) {
486 struct in6_addr prefix = addrs[i].addr.in6;
487 prefix.s6_addr32[1] |= htonl(a->assigned);
488 prefix.s6_addr32[2] = prefix.s6_addr32[3] = 0;
489 netlink_setup_route(&prefix, (a->managed_size) ? addrs[i].prefix : a->length,
490 iface->ifindex, &a->peer.sin6_addr, 1024, add);
491 }
492 }
493
494 static void apply_lease(struct interface *iface, struct dhcp_assignment *a, bool add)
495 {
496 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
497 ssize_t addrlen = (a->managed) ? a->managed_size : (ssize_t)iface->addr6_len;
498
499 __apply_lease(iface, a, addrs, addrlen, add);
500 }
501
502 /* Set border assignment size based on the IPv6 address prefixes */
503 static void set_border_assignment_size(struct interface *iface, struct dhcp_assignment *b)
504 {
505 time_t now = odhcpd_time();
506 int minprefix = -1;
507
508 for (size_t i = 0; i < iface->addr6_len; ++i) {
509 if (iface->addr6[i].preferred > (uint32_t)now &&
510 iface->addr6[i].prefix < 64 &&
511 iface->addr6[i].prefix > minprefix)
512 minprefix = iface->addr6[i].prefix;
513 }
514
515 if (minprefix > 32 && minprefix <= 64)
516 b->assigned = 1U << (64 - minprefix);
517 else
518 b->assigned = 0;
519 }
520
521 /* More data was received from TCP connection */
522 static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
523 {
524 struct ustream_fd *fd = container_of(s, struct ustream_fd, stream);
525 struct dhcp_assignment *c = container_of(fd, struct dhcp_assignment, managed_sock);
526 time_t now = odhcpd_time();
527 bool first = c->managed_size < 0;
528
529 for (;;) {
530 int pending;
531 char *data = ustream_get_read_buf(s, &pending);
532 char *end = memmem(data, pending, "\n\n", 2);
533
534 if (!end)
535 break;
536
537 end += 2;
538 end[-1] = 0;
539
540 c->managed_size = 0;
541 if (c->accept_reconf)
542 c->reconf_cnt = 1;
543
544 char *saveptr;
545 for (char *line = strtok_r(data, "\n", &saveptr); line; line = strtok_r(NULL, "\n", &saveptr)) {
546 c->managed = realloc(c->managed, (c->managed_size + 1) * sizeof(*c->managed));
547 struct odhcpd_ipaddr *n = &c->managed[c->managed_size];
548
549 char *saveptr2, *x = strtok_r(line, "/", &saveptr2);
550 if (!x || inet_pton(AF_INET6, x, &n->addr) < 1)
551 continue;
552
553 x = strtok_r(NULL, ",", &saveptr2);
554 if (sscanf(x, "%hhu", &n->prefix) < 1)
555 continue;
556
557 x = strtok_r(NULL, ",", &saveptr2);
558 if (sscanf(x, "%u", &n->preferred) < 1)
559 continue;
560
561 x = strtok_r(NULL, ",", &saveptr2);
562 if (sscanf(x, "%u", &n->valid) < 1)
563 continue;
564
565 if (n->preferred > n->valid)
566 continue;
567
568 if (UINT32_MAX - now < n->preferred)
569 n->preferred = UINT32_MAX;
570 else
571 n->preferred += now;
572
573 if (UINT32_MAX - now < n->valid)
574 n->valid = UINT32_MAX;
575 else
576 n->valid += now;
577
578 n->dprefix = 0;
579
580 ++c->managed_size;
581 }
582
583 ustream_consume(s, end - data);
584 }
585
586 if (first && c->managed_size == 0)
587 free_dhcpv6_assignment(c);
588 else if (first && !(c->flags & OAF_STATIC))
589 c->valid_until = now + 150;
590 }
591
592
593 /* TCP transmission has ended, either because of success or timeout or other error */
594 static void managed_handle_pd_done(struct ustream *s)
595 {
596 struct ustream_fd *fd = container_of(s, struct ustream_fd, stream);
597 struct dhcp_assignment *c = container_of(fd, struct dhcp_assignment, managed_sock);
598
599 if (!(c->flags & OAF_STATIC))
600 c->valid_until = odhcpd_time() + 15;
601
602 c->managed_size = 0;
603
604 if (c->accept_reconf)
605 c->reconf_cnt = 1;
606 }
607
608 static bool assign_pd(struct interface *iface, struct dhcp_assignment *assign)
609 {
610 struct dhcp_assignment *c;
611
612 if (iface->dhcpv6_pd_manager[0]) {
613 int fd = usock(USOCK_UNIX | USOCK_TCP, iface->dhcpv6_pd_manager, NULL);
614 if (fd >= 0) {
615 struct pollfd pfd = { .fd = fd, .events = POLLIN };
616 char iaidbuf[298];
617
618 odhcpd_hexlify(iaidbuf, assign->clid_data, assign->clid_len);
619
620 assign->managed_sock.stream.notify_read = managed_handle_pd_data;
621 assign->managed_sock.stream.notify_state = managed_handle_pd_done;
622 ustream_fd_init(&assign->managed_sock, fd);
623 ustream_printf(&assign->managed_sock.stream, "%s,%x\n::/%d,0,0\n\n",
624 iaidbuf, assign->iaid, assign->length);
625 ustream_write_pending(&assign->managed_sock.stream);
626 assign->managed_size = -1;
627
628 if (!(assign->flags & OAF_STATIC))
629 assign->valid_until = odhcpd_time() + 15;
630
631 list_add(&assign->head, &iface->ia_assignments);
632
633 /* Wait initial period of up to 250ms for immediate assignment */
634 if (poll(&pfd, 1, 250) < 0) {
635 syslog(LOG_ERR, "poll(): %m");
636 return false;
637 }
638
639 managed_handle_pd_data(&assign->managed_sock.stream, 0);
640
641 if (fcntl(fd, F_GETFL) >= 0 && assign->managed_size > 0)
642 return true;
643 }
644
645 return false;
646 } else if (iface->addr6_len < 1)
647 return false;
648
649 /* Try honoring the hint first */
650 uint32_t current = 1, asize = (1 << (64 - assign->length)) - 1;
651 if (assign->assigned) {
652 list_for_each_entry(c, &iface->ia_assignments, head) {
653 if (c->length == 128 || c->length == 0)
654 continue;
655
656 if (assign->assigned >= current && assign->assigned + asize < c->assigned) {
657 list_add_tail(&assign->head, &c->head);
658
659 if (assign->flags & OAF_BOUND)
660 apply_lease(iface, assign, true);
661
662 return true;
663 }
664
665 if (c->assigned != 0)
666 current = (c->assigned + (1 << (64 - c->length)));
667 }
668 }
669
670 /* Fallback to a variable assignment */
671 current = 1;
672 list_for_each_entry(c, &iface->ia_assignments, head) {
673 if (c->length == 128 || c->length == 0)
674 continue;
675
676 current = (current + asize) & (~asize);
677 if (current + asize < c->assigned) {
678 assign->assigned = current;
679 list_add_tail(&assign->head, &c->head);
680
681 if (assign->flags & OAF_BOUND)
682 apply_lease(iface, assign, true);
683
684 return true;
685 }
686
687 if (c->assigned != 0)
688 current = (c->assigned + (1 << (64 - c->length)));
689 }
690
691 return false;
692 }
693
694 static bool assign_na(struct interface *iface, struct dhcp_assignment *assign)
695 {
696 /* Seed RNG with checksum of DUID */
697 uint32_t seed = 0;
698 for (size_t i = 0; i < assign->clid_len; ++i)
699 seed += assign->clid_data[i];
700 srand(seed);
701
702 /* Try to assign up to 100x */
703 for (size_t i = 0; i < 100; ++i) {
704 uint32_t try;
705 do try = ((uint32_t)rand()) % 0x0fff; while (try < 0x100);
706
707 struct dhcp_assignment *c;
708 list_for_each_entry(c, &iface->ia_assignments, head) {
709 if (c->length == 0)
710 continue;
711
712 if (c->assigned > try || c->length != 128) {
713 assign->assigned = try;
714 list_add_tail(&assign->head, &c->head);
715 return true;
716 } else if (c->assigned == try)
717 break;
718 }
719 }
720
721 return false;
722 }
723
724 static void handle_addrlist_change(struct netevent_handler_info *info)
725 {
726 struct interface *iface = info->iface;
727 struct dhcp_assignment *c, *d, *border = list_last_entry(
728 &iface->ia_assignments, struct dhcp_assignment, head);
729 struct list_head reassign = LIST_HEAD_INIT(reassign);
730 time_t now = odhcpd_time();
731
732 list_for_each_entry(c, &iface->ia_assignments, head) {
733 if (c != border && iface->ra_managed == RA_MANAGED_NO_MFLAG
734 && (c->flags & OAF_BOUND))
735 __apply_lease(iface, c, info->addrs_old.addrs,
736 info->addrs_old.len, false);
737 }
738
739 set_border_assignment_size(iface, border);
740
741 list_for_each_entry_safe(c, d, &iface->ia_assignments, head) {
742 if (c->clid_len == 0 || (!INFINITE_VALID(c->valid_until) && c->valid_until < now) ||
743 c->managed_size)
744 continue;
745
746 if (c->length < 128 && c->assigned >= border->assigned && c != border)
747 list_move(&c->head, &reassign);
748 else if (c != border && (c->flags & OAF_BOUND))
749 apply_lease(iface, c, true);
750
751 if (c->accept_reconf && c->reconf_cnt == 0) {
752 struct dhcp_assignment *a;
753
754 start_reconf(c);
755
756 /* Leave all other assignments of that client alone */
757 list_for_each_entry(a, &iface->ia_assignments, head)
758 if (a != c && a->clid_len == c->clid_len &&
759 !memcmp(a->clid_data, c->clid_data, a->clid_len))
760 a->reconf_cnt = INT_MAX;
761 }
762 }
763
764 while (!list_empty(&reassign)) {
765 c = list_first_entry(&reassign, struct dhcp_assignment, head);
766 list_del(&c->head);
767 if (!assign_pd(iface, c)) {
768 c->assigned = 0;
769 list_add(&c->head, &iface->ia_assignments);
770 }
771 }
772
773 dhcpv6_ia_write_statefile();
774 }
775
776 static void reconf_timeout_cb(struct uloop_timeout *event)
777 {
778 struct dhcp_assignment *a = container_of(event, struct dhcp_assignment, reconf_timer);
779
780 if (a->reconf_cnt > 0 && a->reconf_cnt < DHCPV6_REC_MAX_RC) {
781 send_reconf(a);
782 uloop_timeout_set(&a->reconf_timer,
783 DHCPV6_REC_TIMEOUT << a->reconf_cnt);
784 a->reconf_cnt++;
785 } else
786 stop_reconf(a);
787 }
788
789 static void start_reconf(struct dhcp_assignment *a)
790 {
791 uloop_timeout_set(&a->reconf_timer,
792 DHCPV6_REC_TIMEOUT << a->reconf_cnt);
793 a->reconf_timer.cb = reconf_timeout_cb;
794 a->reconf_cnt++;
795
796 send_reconf(a);
797 }
798
799 static void stop_reconf(struct dhcp_assignment *a)
800 {
801 uloop_timeout_cancel(&a->reconf_timer);
802 a->reconf_cnt = 0;
803 a->reconf_timer.cb = NULL;
804 }
805
806 static void valid_until_cb(struct uloop_timeout *event)
807 {
808 struct interface *iface;
809 time_t now = odhcpd_time();
810
811 avl_for_each_element(&interfaces, iface, avl) {
812 struct dhcp_assignment *a, *n;
813
814 if (iface->dhcpv6 != MODE_SERVER || iface->ia_assignments.next == NULL)
815 continue;
816
817 list_for_each_entry_safe(a, n, &iface->ia_assignments, head) {
818 if (!INFINITE_VALID(a->valid_until) && a->valid_until < now) {
819 if ((a->length < 128 && a->clid_len > 0) ||
820 (a->length == 128 && a->clid_len == 0))
821 free_dhcpv6_assignment(a);
822
823 }
824 }
825 }
826 uloop_timeout_set(event, 1000);
827 }
828
829 static size_t build_ia(uint8_t *buf, size_t buflen, uint16_t status,
830 const struct dhcpv6_ia_hdr *ia, struct dhcp_assignment *a,
831 struct interface *iface, bool request)
832 {
833 struct dhcpv6_ia_hdr o_ia = {
834 .type = ia->type,
835 .len = 0,
836 .iaid = ia->iaid,
837 .t1 = 0,
838 .t2 = 0,
839 };
840 size_t ia_len = sizeof(o_ia);
841 time_t now = odhcpd_time();
842
843 if (buflen < ia_len)
844 return 0;
845
846 if (status) {
847 struct __attribute__((packed)) {
848 uint16_t type;
849 uint16_t len;
850 uint16_t val;
851 } o_status = {
852 .type = htons(DHCPV6_OPT_STATUS),
853 .len = htons(sizeof(o_status) - 4),
854 .val = htons(status),
855 };
856
857 memcpy(buf + ia_len, &o_status, sizeof(o_status));
858 ia_len += sizeof(o_status);
859
860 o_ia.len = htons(ia_len - 4);
861 memcpy(buf, &o_ia, sizeof(o_ia));
862
863 return ia_len;
864 }
865
866 if (a) {
867 uint32_t leasetime;
868
869 if (a->leasetime)
870 leasetime = a->leasetime;
871 else
872 leasetime = iface->dhcpv4_leasetime;
873
874 uint32_t pref = leasetime;
875 uint32_t valid = leasetime;
876
877 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
878 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->addr6_len;
879 size_t m = get_preferred_addr(addrs, addrlen);
880
881 for (size_t i = 0; i < addrlen; ++i) {
882 uint32_t prefix_pref = addrs[i].preferred;
883 uint32_t prefix_valid = addrs[i].valid;
884
885 if (!valid_addr(&addrs[i], now))
886 continue;
887
888 if (prefix_pref != UINT32_MAX)
889 prefix_pref -= now;
890
891 if (prefix_valid != UINT32_MAX)
892 prefix_valid -= now;
893
894 if (a->length < 128) {
895 struct dhcpv6_ia_prefix o_ia_p = {
896 .type = htons(DHCPV6_OPT_IA_PREFIX),
897 .len = htons(sizeof(o_ia_p) - 4),
898 .preferred = htonl(prefix_pref),
899 .valid = htonl(prefix_valid),
900 .prefix = (a->managed_size) ? addrs[i].prefix : a->length,
901 .addr = addrs[i].addr.in6,
902 };
903
904 o_ia_p.addr.s6_addr32[1] |= htonl(a->assigned);
905 o_ia_p.addr.s6_addr32[2] = o_ia_p.addr.s6_addr32[3] = 0;
906
907 if ((a->assigned == 0 && a->managed_size == 0) ||
908 !valid_prefix_length(a, addrs[i].prefix))
909 continue;
910
911 if (buflen < ia_len + sizeof(o_ia_p))
912 return 0;
913
914 memcpy(buf + ia_len, &o_ia_p, sizeof(o_ia_p));
915 ia_len += sizeof(o_ia_p);
916 } else {
917 struct dhcpv6_ia_addr o_ia_a = {
918 .type = htons(DHCPV6_OPT_IA_ADDR),
919 .len = htons(sizeof(o_ia_a) - 4),
920 .addr = addrs[i].addr.in6,
921 .preferred = htonl(prefix_pref),
922 .valid = htonl(prefix_valid)
923 };
924
925 o_ia_a.addr.s6_addr32[3] = htonl(a->assigned);
926
927 if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) ||
928 a->assigned == 0)
929 continue;
930
931 if (buflen < ia_len + sizeof(o_ia_a))
932 return 0;
933
934 memcpy(buf + ia_len, &o_ia_a, sizeof(o_ia_a));
935 ia_len += sizeof(o_ia_a);
936 }
937
938 /* Calculate T1 / T2 based on non-deprecated addresses */
939 if (prefix_pref > 0) {
940 if (prefix_pref < pref)
941 pref = prefix_pref;
942
943 if (prefix_valid < valid)
944 valid = prefix_valid;
945 }
946 }
947
948 if (!INFINITE_VALID(a->valid_until))
949 /* UINT32_MAX is considered as infinite leasetime */
950 a->valid_until = (valid == UINT32_MAX) ? 0 : valid + now;
951
952 o_ia.t1 = htonl((pref == UINT32_MAX) ? pref : pref * 5 / 10);
953 o_ia.t2 = htonl((pref == UINT32_MAX) ? pref : pref * 8 / 10);
954
955 if (!o_ia.t1)
956 o_ia.t1 = htonl(1);
957
958 if (!o_ia.t2)
959 o_ia.t2 = htonl(1);
960 }
961
962 if (!request) {
963 uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
964 uint16_t otype, olen;
965
966 dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
967 struct dhcpv6_ia_prefix *ia_p = (struct dhcpv6_ia_prefix *)&odata[-4];
968 struct dhcpv6_ia_addr *ia_a = (struct dhcpv6_ia_addr *)&odata[-4];
969 bool found = false;
970
971 if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*ia_p) - 4) &&
972 (otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*ia_a) - 4))
973 continue;
974
975 if (a) {
976 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
977 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->addr6_len;
978
979 for (size_t i = 0; i < addrlen; ++i) {
980 if (!valid_addr(&addrs[i], now))
981 continue;
982
983 struct in6_addr addr = addrs[i].addr.in6;
984 if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
985 addr.s6_addr32[1] |= htonl(a->assigned);
986 addr.s6_addr32[2] = addr.s6_addr32[3] = 0;
987
988 if (!memcmp(&ia_p->addr, &addr, sizeof(addr)) &&
989 ia_p->prefix == ((a->managed) ? addrs[i].prefix : a->length))
990 found = true;
991 } else {
992 addr.s6_addr32[3] = htonl(a->assigned);
993
994 if (!memcmp(&ia_a->addr, &addr, sizeof(addr)))
995 found = true;
996 }
997 }
998 }
999
1000 if (!found) {
1001 if (otype == DHCPV6_OPT_IA_PREFIX) {
1002 struct dhcpv6_ia_prefix o_ia_p = {
1003 .type = htons(DHCPV6_OPT_IA_PREFIX),
1004 .len = htons(sizeof(o_ia_p) - 4),
1005 .preferred = 0,
1006 .valid = 0,
1007 .prefix = ia_p->prefix,
1008 .addr = ia_p->addr,
1009 };
1010
1011 if (buflen < ia_len + sizeof(o_ia_p))
1012 return 0;
1013
1014 memcpy(buf + ia_len, &o_ia_p, sizeof(o_ia_p));
1015 ia_len += sizeof(o_ia_p);
1016 } else {
1017 struct dhcpv6_ia_addr o_ia_a = {
1018 .type = htons(DHCPV6_OPT_IA_ADDR),
1019 .len = htons(sizeof(o_ia_a) - 4),
1020 .addr = ia_a->addr,
1021 .preferred = 0,
1022 .valid = 0,
1023 };
1024
1025 if (buflen < ia_len + sizeof(o_ia_a))
1026 continue;
1027
1028 memcpy(buf + ia_len, &o_ia_a, sizeof(o_ia_a));
1029 ia_len += sizeof(o_ia_a);
1030 }
1031 }
1032 }
1033 }
1034
1035 o_ia.len = htons(ia_len - 4);
1036 memcpy(buf, &o_ia, sizeof(o_ia));
1037 return ia_len;
1038 }
1039
1040 struct log_ctxt {
1041 char *buf;
1042 int buf_len;
1043 int buf_idx;
1044 };
1045
1046 static void dhcpv6_log_ia_addr(struct in6_addr *addr, int prefix, _unused uint32_t pref,
1047 _unused uint32_t valid, void *arg)
1048 {
1049 struct log_ctxt *ctxt = (struct log_ctxt *)arg;
1050 char addrbuf[INET6_ADDRSTRLEN];
1051
1052 inet_ntop(AF_INET6, addr, addrbuf, sizeof(addrbuf));
1053 ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx, ctxt->buf_len - ctxt->buf_idx,
1054 "%s/%d ", addrbuf, prefix);
1055 }
1056
1057 static void dhcpv6_log(uint8_t msgtype, struct interface *iface, time_t now,
1058 const char *duidbuf, bool is_pd, struct dhcp_assignment *a, int code)
1059 {
1060 const char *type = "UNKNOWN";
1061 const char *status = "UNKNOWN";
1062
1063 switch (msgtype) {
1064 case DHCPV6_MSG_SOLICIT:
1065 type = "SOLICIT";
1066 break;
1067 case DHCPV6_MSG_REQUEST:
1068 type = "REQUEST";
1069 break;
1070 case DHCPV6_MSG_CONFIRM:
1071 type = "CONFIRM";
1072 break;
1073 case DHCPV6_MSG_RENEW:
1074 type = "RENEW";
1075 break;
1076 case DHCPV6_MSG_REBIND:
1077 type = "REBIND";
1078 break;
1079 case DHCPV6_MSG_RELEASE:
1080 type = "RELEASE";
1081 break;
1082 case DHCPV6_MSG_DECLINE:
1083 type = "DECLINE";
1084 break;
1085 }
1086
1087 switch (code) {
1088 case DHCPV6_STATUS_OK:
1089 status = "ok";
1090 break;
1091 case DHCPV6_STATUS_NOADDRSAVAIL:
1092 status = "no addresses available";
1093 break;
1094 case DHCPV6_STATUS_NOBINDING:
1095 status = "no binding";
1096 break;
1097 case DHCPV6_STATUS_NOTONLINK:
1098 status = "not on-link";
1099 break;
1100 case DHCPV6_STATUS_NOPREFIXAVAIL:
1101 status = "no prefix available";
1102 break;
1103 }
1104
1105 char leasebuf[256] = "";
1106
1107 if (a) {
1108 struct log_ctxt ctxt = {.buf = leasebuf,
1109 .buf_len = sizeof(leasebuf),
1110 .buf_idx = 0 };
1111
1112 dhcpv6_ia_enum_addrs(iface, a, now, dhcpv6_log_ia_addr, &ctxt);
1113 }
1114
1115 syslog(LOG_WARNING, "DHCPV6 %s %s from %s on %s: %s %s", type, (is_pd) ? "IA_PD" : "IA_NA",
1116 duidbuf, iface->name, status, leasebuf);
1117 }
1118
1119 static bool dhcpv6_ia_on_link(const struct dhcpv6_ia_hdr *ia, struct dhcp_assignment *a,
1120 struct interface *iface)
1121 {
1122 struct odhcpd_ipaddr *addrs = (a && a->managed) ? a->managed : iface->addr6;
1123 size_t addrlen = (a && a->managed) ? (size_t)a->managed_size : iface->addr6_len;
1124 time_t now = odhcpd_time();
1125 uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
1126 uint16_t otype, olen;
1127 bool onlink = true;
1128
1129 dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
1130 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix *)&odata[-4];
1131 struct dhcpv6_ia_addr *n = (struct dhcpv6_ia_addr *)&odata[-4];
1132
1133 if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*p) - 4) &&
1134 (otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*n) - 4))
1135 continue;
1136
1137 onlink = false;
1138 for (size_t i = 0; i < addrlen; ++i) {
1139 if (!valid_addr(&addrs[i], now))
1140 continue;
1141
1142 if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
1143 if (p->prefix < addrs[i].prefix ||
1144 odhcpd_bmemcmp(&p->addr, &addrs[i].addr.in6, addrs[i].prefix))
1145 continue;
1146
1147 } else if (odhcpd_bmemcmp(&n->addr, &addrs[i].addr.in6, addrs[i].prefix))
1148 continue;
1149
1150 onlink = true;
1151 }
1152
1153 if (!onlink)
1154 break;
1155 }
1156
1157 return onlink;
1158 }
1159
1160 ssize_t dhcpv6_ia_handle_IAs(uint8_t *buf, size_t buflen, struct interface *iface,
1161 const struct sockaddr_in6 *addr, const void *data, const uint8_t *end)
1162 {
1163 time_t now = odhcpd_time();
1164 size_t response_len = 0;
1165 const struct dhcpv6_client_header *hdr = data;
1166 uint8_t *start = (uint8_t*)&hdr[1], *odata;
1167 uint16_t otype, olen;
1168 /* Find and parse client-id and hostname */
1169 bool accept_reconf = false;
1170 uint8_t *clid_data = NULL, clid_len = 0, mac[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
1171 char hostname[256];
1172 size_t hostname_len = 0;
1173 bool notonlink = false;
1174 char duidbuf[261];
1175
1176 dhcpv6_for_each_option(start, end, otype, olen, odata) {
1177 if (otype == DHCPV6_OPT_CLIENTID) {
1178 clid_data = odata;
1179 clid_len = olen;
1180
1181 if (olen == 14 && odata[0] == 0 && odata[1] == 1)
1182 memcpy(mac, &odata[8], sizeof(mac));
1183 else if (olen == 10 && odata[0] == 0 && odata[1] == 3)
1184 memcpy(mac, &odata[4], sizeof(mac));
1185
1186 if (olen <= 130)
1187 odhcpd_hexlify(duidbuf, odata, olen);
1188 } else if (otype == DHCPV6_OPT_FQDN && olen >= 2 && olen <= 255) {
1189 uint8_t fqdn_buf[256];
1190 memcpy(fqdn_buf, odata, olen);
1191 fqdn_buf[olen++] = 0;
1192
1193 if (dn_expand(&fqdn_buf[1], &fqdn_buf[olen], &fqdn_buf[1], hostname, sizeof(hostname)) > 0)
1194 hostname_len = strcspn(hostname, ".");
1195 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT)
1196 accept_reconf = true;
1197 }
1198
1199 if (!clid_data || !clid_len || clid_len > 130)
1200 goto out;
1201
1202 struct dhcp_assignment *first = NULL;
1203 dhcpv6_for_each_option(start, end, otype, olen, odata) {
1204 bool is_pd = (otype == DHCPV6_OPT_IA_PD);
1205 bool is_na = (otype == DHCPV6_OPT_IA_NA);
1206 bool ia_addr_present = false;
1207 if (!is_pd && !is_na)
1208 continue;
1209
1210 struct dhcpv6_ia_hdr *ia = (struct dhcpv6_ia_hdr*)&odata[-4];
1211 size_t ia_response_len = 0;
1212 uint8_t reqlen = (is_pd) ? 62 : 128;
1213 uint32_t reqhint = 0;
1214
1215 /* Parse request hint for IA-PD */
1216 if (is_pd) {
1217 uint8_t *sdata;
1218 uint16_t stype, slen;
1219 dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1220 if (stype != DHCPV6_OPT_IA_PREFIX || slen < sizeof(struct dhcpv6_ia_prefix) - 4)
1221 continue;
1222
1223 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&sdata[-4];
1224 if (p->prefix) {
1225 reqlen = p->prefix;
1226 reqhint = ntohl(p->addr.s6_addr32[1]);
1227 if (reqlen > 32 && reqlen <= 64)
1228 reqhint &= (1U << (64 - reqlen)) - 1;
1229 }
1230 }
1231
1232 if (reqlen > 64)
1233 reqlen = 64;
1234 } else if (is_na) {
1235 uint8_t *sdata;
1236 uint16_t stype, slen;
1237 dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1238 if (stype != DHCPV6_OPT_IA_ADDR || slen < sizeof(struct dhcpv6_ia_addr) - 4)
1239 continue;
1240
1241 ia_addr_present = true;
1242 }
1243 }
1244
1245 /* Find assignment */
1246 struct dhcp_assignment *c, *a = NULL;
1247 list_for_each_entry(c, &iface->ia_assignments, head) {
1248 if (((c->clid_len == clid_len && !memcmp(c->clid_data, clid_data, clid_len)) ||
1249 (c->clid_len >= clid_len && !c->clid_data[0] && !c->clid_data[1]
1250 && !memcmp(c->mac, mac, sizeof(mac)))) &&
1251 (!(c->flags & (OAF_BOUND|OAF_TENTATIVE)) || c->iaid == ia->iaid) &&
1252 (INFINITE_VALID(c->valid_until) || now < c->valid_until) &&
1253 ((is_pd && c->length <= 64) || (is_na && c->length == 128))) {
1254 a = c;
1255
1256 /* Reset state */
1257 if (a->flags & OAF_BOUND)
1258 apply_lease(iface, a, false);
1259
1260 memcpy(a->clid_data, clid_data, clid_len);
1261 a->clid_len = clid_len;
1262 a->iaid = ia->iaid;
1263 a->peer = *addr;
1264 stop_reconf(a);
1265 break;
1266 }
1267 }
1268
1269 /* Generic message handling */
1270 uint16_t status = DHCPV6_STATUS_OK;
1271 if (a && a->managed_size < 0)
1272 return -1;
1273
1274 if (hdr->msg_type == DHCPV6_MSG_SOLICIT ||
1275 hdr->msg_type == DHCPV6_MSG_REQUEST ||
1276 (hdr->msg_type == DHCPV6_MSG_REBIND && !a)) {
1277 bool assigned = !!a;
1278
1279 if (!a && !iface->no_dynamic_dhcp && (iface->dhcpv6_pd || iface->dhcpv6_na)) {
1280 /* Create new binding */
1281 a = calloc(1, sizeof(*a) + clid_len);
1282 if (a) {
1283 a->clid_len = clid_len;
1284 a->iaid = ia->iaid;
1285 a->length = reqlen;
1286 a->peer = *addr;
1287 a->assigned = reqhint;
1288 /* Set valid time to current time indicating */
1289 /* assignment is not having infinite lifetime */
1290 a->valid_until = now;
1291 a->iface = iface;
1292
1293 if (first)
1294 memcpy(a->key, first->key, sizeof(a->key));
1295 else
1296 odhcpd_urandom(a->key, sizeof(a->key));
1297 memcpy(a->clid_data, clid_data, clid_len);
1298
1299 if (is_pd && iface->dhcpv6_pd)
1300 while (!(assigned = assign_pd(iface, a)) &&
1301 !a->managed_size && ++a->length <= 64);
1302 else if (is_na && iface->dhcpv6_na)
1303 assigned = assign_na(iface, a);
1304
1305 if (a->managed_size && !assigned)
1306 return -1;
1307 }
1308 }
1309
1310 if (!assigned || iface->addr6_len == 0)
1311 /* Set error status */
1312 status = (is_pd) ? DHCPV6_STATUS_NOPREFIXAVAIL : DHCPV6_STATUS_NOADDRSAVAIL;
1313 else if (hdr->msg_type == DHCPV6_MSG_REQUEST && !dhcpv6_ia_on_link(ia, a, iface)) {
1314 /* Send NOTONLINK staus for the IA */
1315 status = DHCPV6_STATUS_NOTONLINK;
1316 assigned = false;
1317 } else if (accept_reconf && assigned && !first &&
1318 hdr->msg_type != DHCPV6_MSG_REBIND) {
1319 size_t handshake_len = 4;
1320 buf[0] = 0;
1321 buf[1] = DHCPV6_OPT_RECONF_ACCEPT;
1322 buf[2] = 0;
1323 buf[3] = 0;
1324
1325 if (hdr->msg_type == DHCPV6_MSG_REQUEST) {
1326 struct dhcpv6_auth_reconfigure auth = {
1327 htons(DHCPV6_OPT_AUTH),
1328 htons(sizeof(auth) - 4),
1329 3, 1, 0,
1330 {htonl(time(NULL)), htonl(++serial)},
1331 1,
1332 {0}
1333 };
1334 memcpy(auth.key, a->key, sizeof(a->key));
1335 memcpy(buf + handshake_len, &auth, sizeof(auth));
1336 handshake_len += sizeof(auth);
1337 }
1338
1339
1340 buf += handshake_len;
1341 buflen -= handshake_len;
1342 response_len += handshake_len;
1343
1344 first = a;
1345 }
1346
1347 ia_response_len = build_ia(buf, buflen, status, ia, a, iface,
1348 hdr->msg_type == DHCPV6_MSG_REBIND ? false : true);
1349
1350 /* Was only a solicitation: mark binding for removal */
1351 if (assigned && hdr->msg_type == DHCPV6_MSG_SOLICIT) {
1352 a->flags &= ~OAF_BOUND;
1353 a->flags |= OAF_TENTATIVE;
1354
1355 if (!(a->flags & OAF_STATIC))
1356 /* Keep tentative assignment around for 60 seconds */
1357 a->valid_until = now + 60;
1358 } else if (assigned &&
1359 (hdr->msg_type == DHCPV6_MSG_REQUEST ||
1360 hdr->msg_type == DHCPV6_MSG_REBIND)) {
1361 if (hostname_len > 0) {
1362 a->hostname = realloc(a->hostname, hostname_len + 1);
1363 if (a->hostname) {
1364 memcpy(a->hostname, hostname, hostname_len);
1365 a->hostname[hostname_len] = 0;
1366
1367 if (odhcpd_valid_hostname(a->hostname))
1368 a->flags &= ~OAF_BROKEN_HOSTNAME;
1369 else
1370 a->flags |= OAF_BROKEN_HOSTNAME;
1371 }
1372 }
1373 a->accept_reconf = accept_reconf;
1374 a->flags &= ~OAF_TENTATIVE;
1375 a->flags |= OAF_BOUND;
1376 apply_lease(iface, a, true);
1377 } else if (!assigned && a && a->managed_size == 0) {
1378 /* Cleanup failed assignment */
1379 free_dhcpv6_assignment(a);
1380 a = NULL;
1381 }
1382 } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1383 hdr->msg_type == DHCPV6_MSG_RELEASE ||
1384 hdr->msg_type == DHCPV6_MSG_REBIND ||
1385 hdr->msg_type == DHCPV6_MSG_DECLINE) {
1386 if (!a && hdr->msg_type != DHCPV6_MSG_REBIND) {
1387 status = DHCPV6_STATUS_NOBINDING;
1388 ia_response_len = build_ia(buf, buflen, status, ia, a, iface, false);
1389 } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1390 hdr->msg_type == DHCPV6_MSG_REBIND) {
1391 ia_response_len = build_ia(buf, buflen, status, ia, a, iface, false);
1392 if (a) {
1393 a->flags |= OAF_BOUND;
1394 apply_lease(iface, a, true);
1395 }
1396 } else if (hdr->msg_type == DHCPV6_MSG_RELEASE) {
1397 if (!(a->flags & OAF_STATIC))
1398 a->valid_until = now - 1;
1399
1400 if (a->flags & OAF_BOUND) {
1401 apply_lease(iface, a, false);
1402 a->flags &= ~OAF_BOUND;
1403 }
1404 } else if (hdr->msg_type == DHCPV6_MSG_DECLINE && a->length == 128) {
1405 a->flags &= ~OAF_BOUND;
1406
1407 if (!(a->flags & OAF_STATIC)) {
1408 a->clid_len = 0;
1409 a->valid_until = now + 3600; /* Block address for 1h */
1410 }
1411 }
1412 } else if (hdr->msg_type == DHCPV6_MSG_CONFIRM) {
1413 if (ia_addr_present && !dhcpv6_ia_on_link(ia, a, iface)) {
1414 notonlink = true;
1415 break;
1416 }
1417
1418 if (!ia_addr_present || !a || !(a->flags & OAF_BOUND)) {
1419 response_len = 0;
1420 goto out;
1421 }
1422 }
1423
1424 buf += ia_response_len;
1425 buflen -= ia_response_len;
1426 response_len += ia_response_len;
1427 dhcpv6_log(hdr->msg_type, iface, now, duidbuf, is_pd, a, status);
1428 }
1429
1430 switch (hdr->msg_type) {
1431 case DHCPV6_MSG_RELEASE:
1432 case DHCPV6_MSG_DECLINE:
1433 case DHCPV6_MSG_CONFIRM:
1434 if (response_len + 6 < buflen) {
1435 buf[0] = 0;
1436 buf[1] = DHCPV6_OPT_STATUS;
1437 buf[2] = 0;
1438 buf[3] = 2;
1439 buf[4] = 0;
1440 buf[5] = (notonlink) ? DHCPV6_STATUS_NOTONLINK : DHCPV6_STATUS_OK;
1441 response_len += 6;
1442 }
1443 break;
1444
1445 default:
1446 break;
1447 }
1448
1449 dhcpv6_ia_write_statefile();
1450
1451 out:
1452 return response_len;
1453 }
OpenWrt DHCP Server