remove leftover fallout from prefix class support
[project/odhcpd.git] / src / dhcpv6-ia.c
1 /**
2  * Copyright (C) 2013 Steven Barth <steven@midlink.org>
3  *
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.
7  *
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.
12  *
13  */
14
15 #include "odhcpd.h"
16 #include "dhcpv6.h"
17 #include "dhcpv4.h"
18 #include "libubox/md5.h"
19 #include "libubox/usock.h"
20
21 #include <time.h>
22 #include <errno.h>
23 #include <fcntl.h>
24 #include <stdio.h>
25 #include <poll.h>
26 #include <alloca.h>
27 #include <resolv.h>
28 #include <limits.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <unistd.h>
32 #include <stdbool.h>
33 #include <arpa/inet.h>
34 #include <sys/timerfd.h>
35
36
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];
42
43
44 int dhcpv6_ia_init(void)
45 {
46         uloop_timeout_set(&reconf_event, 2000);
47         return 0;
48 }
49
50
51 void free_dhcpv6_assignment(struct dhcpv6_assignment *c)
52 {
53         if (c->managed_sock.fd.registered) {
54                 ustream_free(&c->managed_sock.stream);
55                 close(c->managed_sock.fd.fd);
56         }
57
58         if (c->head.next)
59                 list_del(&c->head);
60
61         free(c->managed);
62         free(c->hostname);
63         free(c);
64 }
65
66
67 int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
68 {
69         if (!enable && iface->ia_assignments.next) {
70                 struct dhcpv6_assignment *c;
71                 while (!list_empty(&iface->ia_assignments)) {
72                         c = list_first_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
73                         free_dhcpv6_assignment(c);
74                 }
75         }
76
77         if (iface->dhcpv6 == RELAYD_SERVER) {
78                 if (!iface->ia_assignments.next)
79                         INIT_LIST_HEAD(&iface->ia_assignments);
80
81                 if (list_empty(&iface->ia_assignments)) {
82                         struct dhcpv6_assignment *border = calloc(1, sizeof(*border));
83                         if (!border) {
84                                 syslog(LOG_ERR, "Calloc failed for border on interface %s", iface->ifname);
85                                 return -1;
86                         }
87                         
88                         border->length = 64;
89                         list_add(&border->head, &iface->ia_assignments);
90                 }
91
92                 update(iface);
93
94                 // Parse static entries
95                 struct lease *lease;
96                 list_for_each_entry(lease, &leases, head) {
97                         // Construct entry
98                         struct dhcpv6_assignment *a = calloc(1, sizeof(*a) + lease->duid_len);
99                         if (!a) {
100                                 syslog(LOG_ERR, "Calloc failed for static lease assignment on interface %s",
101                                         iface->ifname);
102                                 return -1;
103                         }
104
105                         a->clid_len = lease->duid_len;
106                         a->length = 128;
107                         if (lease->hostid) {
108                                 a->assigned = lease->hostid;
109                         } else {
110                                 uint32_t i4a = ntohl(lease->ipaddr.s_addr) & 0xff;
111                                 a->assigned = ((i4a / 100) << 8) | (((i4a % 100) / 10) << 4) | (i4a % 10);
112                         }
113                         odhcpd_urandom(a->key, sizeof(a->key));
114                         memcpy(a->clid_data, lease->duid, a->clid_len);
115                         memcpy(a->mac, lease->mac.ether_addr_octet, sizeof(a->mac));
116
117                         // Assign to all interfaces
118                         struct dhcpv6_assignment *c;
119                         list_for_each_entry(c, &iface->ia_assignments, head) {
120                                 if (c->length != 128 || c->assigned > a->assigned) {
121                                         list_add_tail(&a->head, &c->head);
122                                         break;
123                                 } else if (c->assigned == a->assigned) {
124                                         // Already an assignment with that number
125                                         break;
126                                 }
127                         }
128
129                         if (a->head.next) {
130                                 if (lease->hostname[0]) {
131                                         free(a->hostname);
132                                         a->hostname = strdup(lease->hostname);
133                                 }
134                         } else {
135                                 free(a->hostname);
136                                 free(a);
137                         }
138                 }
139         }
140         return 0;
141 }
142
143
144 static int send_reconf(struct interface *iface, struct dhcpv6_assignment *assign)
145 {
146         struct {
147                 struct dhcpv6_client_header hdr;
148                 uint16_t srvid_type;
149                 uint16_t srvid_len;
150                 uint16_t duid_type;
151                 uint16_t hardware_type;
152                 uint8_t mac[6];
153                 uint16_t msg_type;
154                 uint16_t msg_len;
155                 uint8_t msg_id;
156                 struct dhcpv6_auth_reconfigure auth;
157                 uint16_t clid_type;
158                 uint16_t clid_len;
159                 uint8_t clid_data[128];
160         } __attribute__((packed)) reconf_msg = {
161                 .hdr = {DHCPV6_MSG_RECONFIGURE, {0, 0, 0}},
162                 .srvid_type = htons(DHCPV6_OPT_SERVERID),
163                 .srvid_len = htons(10),
164                 .duid_type = htons(3),
165                 .hardware_type = htons(1),
166                 .msg_type = htons(DHCPV6_OPT_RECONF_MSG),
167                 .msg_len = htons(1),
168                 .msg_id = DHCPV6_MSG_RENEW,
169                 .auth = {htons(DHCPV6_OPT_AUTH),
170                                 htons(sizeof(reconf_msg.auth) - 4), 3, 1, 0,
171                                 {htonl(time(NULL)), htonl(++serial)}, 2, {0}},
172                 .clid_type = htons(DHCPV6_OPT_CLIENTID),
173                 .clid_len = htons(assign->clid_len),
174                 .clid_data = {0},
175         };
176
177         odhcpd_get_mac(iface, reconf_msg.mac);
178         memcpy(reconf_msg.clid_data, assign->clid_data, assign->clid_len);
179         struct iovec iov = {&reconf_msg, sizeof(reconf_msg) - 128 + assign->clid_len};
180
181         md5_ctx_t md5;
182         uint8_t secretbytes[64];
183         memset(secretbytes, 0, sizeof(secretbytes));
184         memcpy(secretbytes, assign->key, sizeof(assign->key));
185
186         for (size_t i = 0; i < sizeof(secretbytes); ++i)
187                 secretbytes[i] ^= 0x36;
188
189         md5_begin(&md5);
190         md5_hash(secretbytes, sizeof(secretbytes), &md5);
191         md5_hash(iov.iov_base, iov.iov_len, &md5);
192         md5_end(reconf_msg.auth.key, &md5);
193
194         for (size_t i = 0; i < sizeof(secretbytes); ++i) {
195                 secretbytes[i] ^= 0x36;
196                 secretbytes[i] ^= 0x5c;
197         }
198
199         md5_begin(&md5);
200         md5_hash(secretbytes, sizeof(secretbytes), &md5);
201         md5_hash(reconf_msg.auth.key, 16, &md5);
202         md5_end(reconf_msg.auth.key, &md5);
203
204         return odhcpd_send(iface->dhcpv6_event.uloop.fd, &assign->peer, &iov, 1, iface);
205 }
206
207
208 void dhcpv6_write_statefile(void)
209 {
210         md5_ctx_t md5;
211         md5_begin(&md5);
212
213         if (config.dhcp_statefile) {
214                 time_t now = odhcpd_time(), wall_time = time(NULL);
215                 int fd = open(config.dhcp_statefile, O_CREAT | O_WRONLY | O_CLOEXEC, 0644);
216                 if (fd < 0)
217                         return;
218
219                 lockf(fd, F_LOCK, 0);
220                 if (ftruncate(fd, 0) < 0) {}
221
222                 FILE *fp = fdopen(fd, "w");
223                 if (!fp) {
224                         close(fd);
225                         return;
226                 }
227
228                 struct interface *iface;
229                 list_for_each_entry(iface, &interfaces, head) {
230                         if (iface->dhcpv6 != RELAYD_SERVER && iface->dhcpv4 != RELAYD_SERVER)
231                                 continue;
232
233                         if (iface->dhcpv6 == RELAYD_SERVER && iface->ia_assignments.next) {
234                                 struct dhcpv6_assignment *c;
235                                 list_for_each_entry(c, &iface->ia_assignments, head) {
236                                         if (c->clid_len == 0 || c->managed_size < 0)
237                                                 continue;
238
239                                         char ipbuf[INET6_ADDRSTRLEN];
240                                         char leasebuf[512];
241                                         char duidbuf[264];
242                                         odhcpd_hexlify(duidbuf, c->clid_data, c->clid_len);
243
244                                         // iface DUID iaid hostname lifetime assigned length [addrs...]
245                                         int l = snprintf(leasebuf, sizeof(leasebuf), "# %s %s %x %s %u %x %u ",
246                                                         iface->ifname, duidbuf, ntohl(c->iaid),
247                                                         (c->hostname ? c->hostname : "-"),
248                                                         (unsigned)(c->valid_until > now ?
249                                                                         (c->valid_until - now + wall_time) : 0),
250                                                         c->assigned, (unsigned)c->length);
251
252                                         struct in6_addr addr;
253                                         struct odhcpd_ipaddr *addrs = (c->managed) ? c->managed : iface->ia_addr;
254                                         size_t addrlen = (c->managed) ? (size_t)c->managed_size : iface->ia_addr_len;
255                                         size_t m = 0;
256
257                                         for (size_t i = 0; i < addrlen; ++i)
258                                                 if (addrs[i].preferred > addrs[m].preferred ||
259                                                                 (addrs[i].preferred == addrs[m].preferred &&
260                                                                                 memcmp(&addrs[i].addr, &addrs[m].addr, 16) > 0))
261                                                         m = i;
262
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 != m &&
266                                                                                 addrs[i].prefix == 64))
267                                                         continue;
268
269                                                 addr = addrs[i].addr;
270                                                 if (c->length == 128)
271                                                         addr.s6_addr32[3] = htonl(c->assigned);
272                                                 else
273                                                         addr.s6_addr32[1] |= htonl(c->assigned);
274
275                                                 inet_ntop(AF_INET6, &addr, ipbuf, sizeof(ipbuf) - 1);
276
277                                                 if (c->length == 128 && c->hostname) {
278                                                         fputs(ipbuf, fp);
279
280                                                         char b[256];
281                                                         if (dn_expand(iface->search, iface->search + iface->search_len,
282                                                                         iface->search, b, sizeof(b)) > 0)
283                                                                 fprintf(fp, "\t%s.%s", c->hostname, b);
284
285                                                         fprintf(fp, "\t%s\n", c->hostname);
286                                                         md5_hash(ipbuf, strlen(ipbuf), &md5);
287                                                         md5_hash(c->hostname, strlen(c->hostname), &md5);
288                                                 }
289
290                                                 l += snprintf(leasebuf + l, sizeof(leasebuf) - l, "%s/%d ", ipbuf,
291                                                                 (c->managed_size) ? addrs[i].prefix : c->length);
292                                         }
293                                         leasebuf[l - 1] = '\n';
294                                         fwrite(leasebuf, 1, l, fp);
295                                 }
296                         }
297
298                         if (iface->dhcpv4 == RELAYD_SERVER && iface->dhcpv4_assignments.next) {
299                                 struct dhcpv4_assignment *c;
300                                 list_for_each_entry(c, &iface->dhcpv4_assignments, head) {
301                                         char ipbuf[INET6_ADDRSTRLEN];
302                                         char leasebuf[512];
303                                         char duidbuf[16];
304                                         odhcpd_hexlify(duidbuf, c->hwaddr, sizeof(c->hwaddr));
305
306                                         // iface DUID iaid hostname lifetime assigned length [addrs...]
307                                         int l = snprintf(leasebuf, sizeof(leasebuf), "# %s %s ipv4 %s %u %x 32 ",
308                                                         iface->ifname, duidbuf,
309                                                         (c->hostname ? c->hostname : "-"),
310                                                         (unsigned)(c->valid_until > now ?
311                                                                         (c->valid_until - now + wall_time) : 0),
312                                                         c->addr);
313
314                                         struct in_addr addr = {htonl(c->addr)};
315                                         inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf) - 1);
316
317                                         if (c->hostname[0]) {
318                                                 fputs(ipbuf, fp);
319
320                                                 char b[256];
321                                                 if (dn_expand(iface->search, iface->search + iface->search_len,
322                                                                 iface->search, b, sizeof(b)) > 0)
323                                                         fprintf(fp, "\t%s.%s", c->hostname, b);
324
325                                                 fprintf(fp, "\t%s\n", c->hostname);
326                                                 md5_hash(ipbuf, strlen(ipbuf), &md5);
327                                                 md5_hash(c->hostname, strlen(c->hostname), &md5);
328                                         }
329
330                                         l += snprintf(leasebuf + l, sizeof(leasebuf) - l, "%s/32 ", ipbuf);
331                                         leasebuf[l - 1] = '\n';
332                                         fwrite(leasebuf, 1, l, fp);
333                                 }
334                         }
335                 }
336
337                 fclose(fp);
338         }
339
340         uint8_t newmd5[16];
341         md5_end(newmd5, &md5);
342
343         if (config.dhcp_cb && memcmp(newmd5, statemd5, sizeof(newmd5))) {
344                 memcpy(statemd5, newmd5, sizeof(statemd5));
345                 char *argv[2] = {config.dhcp_cb, NULL};
346                 if (!vfork()) {
347                         execv(argv[0], argv);
348                         _exit(128);
349                 }
350         }
351 }
352
353
354 static void apply_lease(struct interface *iface, struct dhcpv6_assignment *a, bool add)
355 {
356         if (a->length > 64 || a->managed_size < 0)
357                 return;
358
359         struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
360         size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
361
362         for (size_t i = 0; i < addrlen; ++i) {
363                 struct in6_addr prefix = addrs[i].addr;
364                 prefix.s6_addr32[1] |= htonl(a->assigned);
365                 odhcpd_setup_route(&prefix, (a->managed_size) ? addrs[i].prefix : a->length,
366                                 iface, &a->peer.sin6_addr, add);
367         }
368 }
369
370
371 // More data was received from TCP connection
372 static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
373 {
374         struct dhcpv6_assignment *c = container_of(s, struct dhcpv6_assignment, managed_sock);
375         time_t now = odhcpd_time();
376         bool first = c->managed_size < 0;
377
378         for (;;) {
379                 int pending;
380                 char *data = ustream_get_read_buf(s, &pending);
381                 char *end = memmem(data, pending, "\n\n", 2);
382
383                 if (!end)
384                         break;
385
386                 end += 2;
387                 end[-1] = 0;
388
389                 c->managed_size = 0;
390                 if (c->accept_reconf)
391                         c->reconf_cnt = 1;
392
393                 char *saveptr;
394                 for (char *line = strtok_r(data, "\n", &saveptr); line; line = strtok_r(NULL, "\n", &saveptr)) {
395                         c->managed = realloc(c->managed, (c->managed_size + 1) * sizeof(*c->managed));
396                         struct odhcpd_ipaddr *n = &c->managed[c->managed_size];
397
398                         char *saveptr2, *x = strtok_r(line, "/", &saveptr2);
399                         if (!x || inet_pton(AF_INET6, x, &n->addr) < 1)
400                                 continue;
401
402                         x = strtok_r(NULL, ",", &saveptr2);
403                         if (sscanf(x, "%hhu", &n->prefix) < 1)
404                                 continue;
405
406                         x = strtok_r(NULL, ",", &saveptr2);
407                         if (sscanf(x, "%u", &n->preferred) < 1)
408                                 continue;
409
410                         x = strtok_r(NULL, ",", &saveptr2);
411                         if (sscanf(x, "%u", &n->valid) < 1)
412                                 continue;
413
414                         if (n->preferred > n->valid)
415                                 continue;
416
417                         if (UINT32_MAX - now < n->preferred)
418                                 n->preferred = UINT32_MAX;
419                         else
420                                 n->preferred += now;
421
422                         if (UINT32_MAX - now < n->valid)
423                                 n->valid = UINT32_MAX;
424                         else
425                                 n->valid += now;
426
427                         n->dprefix = 0;
428
429                         ++c->managed_size;
430                 }
431
432                 ustream_consume(s, end - data);
433         }
434
435         if (first && c->managed_size == 0)
436                 free_dhcpv6_assignment(c);
437         else if (first)
438                 c->valid_until = now + 150;
439 }
440
441
442 // TCP transmission has ended, either because of success or timeout or other error
443 static void managed_handle_pd_done(struct ustream *s)
444 {
445         struct dhcpv6_assignment *c = container_of(s, struct dhcpv6_assignment, managed_sock);
446         c->valid_until = odhcpd_time() + 15;
447         c->managed_size = 0;
448         if (c->accept_reconf)
449                 c->reconf_cnt = 1;
450 }
451
452
453
454 static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
455 {
456         struct dhcpv6_assignment *c;
457
458         if (iface->dhcpv6_pd_manager[0]) {
459                 int fd = usock(USOCK_UNIX | USOCK_TCP, iface->dhcpv6_pd_manager, NULL);
460                 if (fd >= 0) {
461                         char iaidbuf[298];
462                         odhcpd_hexlify(iaidbuf, assign->clid_data, assign->clid_len);
463
464                         assign->managed_sock.stream.notify_read = managed_handle_pd_data;
465                         assign->managed_sock.stream.notify_state = managed_handle_pd_done;
466                         ustream_fd_init(&assign->managed_sock, fd);
467                         ustream_printf(&assign->managed_sock.stream, "%s,%x\n::/%d,0,0\n\n",
468                                         iaidbuf, assign->iaid, assign->length);
469                         ustream_write_pending(&assign->managed_sock.stream);
470                         assign->managed_size = -1;
471                         assign->valid_until = odhcpd_time() + 15;
472                         list_add(&assign->head, &iface->ia_assignments);
473
474                         // Wait initial period of up to 250ms for immediate assignment
475                         struct pollfd pfd = { .fd = fd, .events = POLLIN };
476                         poll(&pfd, 1, 250);
477                         managed_handle_pd_data(&assign->managed_sock.stream, 0);
478
479                         if (fcntl(fd, F_GETFL) >= 0 && assign->managed_size > 0)
480                                 return true;
481                 }
482
483                 return false;
484         } else if (iface->ia_addr_len < 1) {
485                 return false;
486         }
487
488         // Try honoring the hint first
489         uint32_t current = 1, asize = (1 << (64 - assign->length)) - 1;
490         if (assign->assigned) {
491                 list_for_each_entry(c, &iface->ia_assignments, head) {
492                         if (c->length == 128 || c->length == 0)
493                                 continue;
494
495                         if (assign->assigned >= current && assign->assigned + asize < c->assigned) {
496                                 list_add_tail(&assign->head, &c->head);
497                                 apply_lease(iface, assign, true);
498                                 return true;
499                         }
500
501                         if (c->assigned != 0)
502                                 current = (c->assigned + (1 << (64 - c->length)));
503                 }
504         }
505
506         // Fallback to a variable assignment
507         current = 1;
508         list_for_each_entry(c, &iface->ia_assignments, head) {
509                 if (c->length == 128 || c->length == 0)
510                         continue;
511
512                 current = (current + asize) & (~asize);
513                 if (current + asize < c->assigned) {
514                         assign->assigned = current;
515                         list_add_tail(&assign->head, &c->head);
516                         apply_lease(iface, assign, true);
517                         return true;
518                 }
519
520                 if (c->assigned != 0)
521                         current = (c->assigned + (1 << (64 - c->length)));
522         }
523
524         return false;
525 }
526
527
528 static bool assign_na(struct interface *iface, struct dhcpv6_assignment *assign)
529 {
530         // Seed RNG with checksum of DUID
531         uint32_t seed = 0;
532         for (size_t i = 0; i < assign->clid_len; ++i)
533                 seed += assign->clid_data[i];
534         srand(seed);
535
536         // Try to assign up to 100x
537         for (size_t i = 0; i < 100; ++i) {
538                 uint32_t try;
539                 do try = ((uint32_t)rand()) % 0x0fff; while (try < 0x100);
540
541                 struct dhcpv6_assignment *c;
542                 list_for_each_entry(c, &iface->ia_assignments, head) {
543                         if (c->length == 0)
544                                 continue;
545
546                         if (c->assigned > try || c->length != 128) {
547                                 assign->assigned = try;
548                                 list_add_tail(&assign->head, &c->head);
549                                 return true;
550                         } else if (c->assigned == try) {
551                                 break;
552                         }
553                 }
554         }
555
556         return false;
557 }
558
559
560 static int prefixcmp(const void *va, const void *vb)
561 {
562         const struct odhcpd_ipaddr *a = va, *b = vb;
563         uint32_t a_pref = ((a->addr.s6_addr[0] & 0xfe) != 0xfc) ? a->preferred : 1;
564         uint32_t b_pref = ((b->addr.s6_addr[0] & 0xfe) != 0xfc) ? b->preferred : 1;
565         return (a_pref < b_pref) ? 1 : (a_pref > b_pref) ? -1 : 0;
566 }
567
568
569 static void update(struct interface *iface)
570 {
571         struct odhcpd_ipaddr addr[8];
572         memset(addr, 0, sizeof(addr));
573         int len = odhcpd_get_interface_addresses(iface->ifindex, addr, 8);
574
575         if (len < 0)
576                 return;
577
578         qsort(addr, len, sizeof(*addr), prefixcmp);
579
580         time_t now = odhcpd_time();
581         int minprefix = -1;
582
583         for (int i = 0; i < len; ++i) {
584                 if (addr[i].preferred > 0 && addr[i].prefix > minprefix)
585                         minprefix = addr[i].prefix;
586
587                 addr[i].addr.s6_addr32[3] = 0;
588
589                 if (addr[i].preferred < UINT32_MAX - now)
590                         addr[i].preferred += now;
591
592                 if (addr[i].valid < UINT32_MAX - now)
593                         addr[i].valid += now;
594         }
595
596         struct dhcpv6_assignment *border = list_last_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
597         if (minprefix > 32 && minprefix <= 64)
598                 border->assigned = 1U << (64 - minprefix);
599         else
600                 border->assigned = 0;
601
602         bool change = len != (int)iface->ia_addr_len;
603         for (int i = 0; !change && i < len; ++i)
604                 if (addr[i].addr.s6_addr32[0] != iface->ia_addr[i].addr.s6_addr32[0] ||
605                                 addr[i].addr.s6_addr32[1] != iface->ia_addr[i].addr.s6_addr32[1] ||
606                                 (addr[i].preferred > 0) != (iface->ia_addr[i].preferred > 0) ||
607                                 (addr[i].valid > (uint32_t)now + 7200) !=
608                                                 (iface->ia_addr[i].valid > (uint32_t)now + 7200))
609                         change = true;
610
611         if (change) {
612                 struct dhcpv6_assignment *c;
613                 list_for_each_entry(c, &iface->ia_assignments, head)
614                         if (c != border && !iface->managed)
615                                 apply_lease(iface, c, false);
616         }
617
618         memcpy(iface->ia_addr, addr, len * sizeof(*addr));
619         iface->ia_addr_len = len;
620
621         if (change) { // Addresses / prefixes have changed
622                 struct list_head reassign = LIST_HEAD_INIT(reassign);
623                 struct dhcpv6_assignment *c, *d;
624                 list_for_each_entry_safe(c, d, &iface->ia_assignments, head) {
625                         if (c->clid_len == 0 || c->valid_until < now || c->managed_size)
626                                 continue;
627
628                         if (c->length < 128 && c->assigned >= border->assigned && c != border)
629                                 list_move(&c->head, &reassign);
630                         else if (c != border)
631                                 apply_lease(iface, c, true);
632
633                         if (c->accept_reconf && c->reconf_cnt == 0) {
634                                 c->reconf_cnt = 1;
635                                 c->reconf_sent = now;
636                                 send_reconf(iface, c);
637
638                                 // Leave all other assignments of that client alone
639                                 struct dhcpv6_assignment *a;
640                                 list_for_each_entry(a, &iface->ia_assignments, head)
641                                         if (a != c && a->clid_len == c->clid_len &&
642                                                         !memcmp(a->clid_data, c->clid_data, a->clid_len))
643                                                 c->reconf_cnt = INT_MAX;
644                         }
645                 }
646
647                 while (!list_empty(&reassign)) {
648                         c = list_first_entry(&reassign, struct dhcpv6_assignment, head);
649                         list_del(&c->head);
650                         if (!assign_pd(iface, c)) {
651                                 c->assigned = 0;
652                                 list_add(&c->head, &iface->ia_assignments);
653                         }
654                 }
655
656                 dhcpv6_write_statefile();
657         }
658 }
659
660
661 static void reconf_timer(struct uloop_timeout *event)
662 {
663         time_t now = odhcpd_time();
664         struct interface *iface;
665         list_for_each_entry(iface, &interfaces, head) {
666                 if (iface->dhcpv6 != RELAYD_SERVER || iface->ia_assignments.next == NULL)
667                         continue;
668
669                 struct dhcpv6_assignment *a, *n;
670                 list_for_each_entry_safe(a, n, &iface->ia_assignments, head) {
671                         if (a->valid_until < now) {
672                                 if ((a->length < 128 && a->clid_len > 0) ||
673                                                 (a->length == 128 && a->clid_len == 0)) {
674                                         list_del(&a->head);
675                                         free_dhcpv6_assignment(a);
676                                 }
677                         } else if (a->reconf_cnt > 0 && a->reconf_cnt < 8 &&
678                                         now > a->reconf_sent + (1 << a->reconf_cnt)) {
679                                 ++a->reconf_cnt;
680                                 a->reconf_sent = now;
681                                 send_reconf(iface, a);
682                         }
683                 }
684         }
685         uloop_timeout_set(event, 2000);
686 }
687
688
689 static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
690                 const struct dhcpv6_ia_hdr *ia, struct dhcpv6_assignment *a,
691                 struct interface *iface, bool request)
692 {
693         if (buflen < sizeof(*ia) + sizeof(struct dhcpv6_ia_prefix))
694                 return 0;
695
696         struct dhcpv6_ia_hdr out = {ia->type, 0, ia->iaid, 0, 0};
697         size_t datalen = sizeof(out);
698         time_t now = odhcpd_time();
699
700         if (status) {
701                 struct __attribute__((packed)) {
702                         uint16_t type;
703                         uint16_t len;
704                         uint16_t value;
705                 } stat = {htons(DHCPV6_OPT_STATUS), htons(sizeof(stat) - 4),
706                                 htons(status)};
707
708                 memcpy(buf + datalen, &stat, sizeof(stat));
709                 datalen += sizeof(stat);
710         } else {
711                 if (a) {
712                         uint32_t leasetime = iface->dhcpv4_leasetime;
713                         if (leasetime == 0)
714                                 leasetime = 3600;
715                         else if (leasetime < 60)
716                                 leasetime = 60;
717
718                         uint32_t pref = leasetime;
719                         uint32_t valid = leasetime;
720
721                         struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
722                         size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
723                         size_t m = 0;
724
725                         for (size_t i = 0; i < addrlen; ++i)
726                                 if (addrs[i].preferred > addrs[m].preferred ||
727                                                 (addrs[i].preferred == addrs[m].preferred &&
728                                                                 memcmp(&addrs[i].addr, &addrs[m].addr, 16) > 0))
729                                         m = i;
730
731                         for (size_t i = 0; i < addrlen; ++i) {
732                                 uint32_t prefix_pref = addrs[i].preferred;
733                                 uint32_t prefix_valid = addrs[i].valid;
734
735                                 if (addrs[i].prefix > 96 ||
736                                                 addrs[i].preferred <= (uint32_t)now)
737                                         continue;
738
739                                 if (prefix_pref != UINT32_MAX)
740                                         prefix_pref -= now;
741
742                                 if (prefix_valid != UINT32_MAX)
743                                         prefix_valid -= now;
744
745                                 if (a->length < 128) {
746                                         struct dhcpv6_ia_prefix p = {
747                                                 .type = htons(DHCPV6_OPT_IA_PREFIX),
748                                                 .len = htons(sizeof(p) - 4),
749                                                 .preferred = htonl(prefix_pref),
750                                                 .valid = htonl(prefix_valid),
751                                                 .prefix = (a->managed_size) ? addrs[i].prefix : a->length,
752                                                 .addr = addrs[i].addr
753                                         };
754                                         p.addr.s6_addr32[1] |= htonl(a->assigned);
755
756                                         size_t entrlen = sizeof(p) - 4;
757
758                                         if (datalen + entrlen + 4 > buflen ||
759                                                         (a->assigned == 0 && a->managed_size == 0))
760                                                 continue;
761
762                                         memcpy(buf + datalen, &p, sizeof(p));
763                                         datalen += entrlen + 4;
764                                 } else {
765                                         struct dhcpv6_ia_addr n = {
766                                                 .type = htons(DHCPV6_OPT_IA_ADDR),
767                                                 .len = htons(sizeof(n) - 4),
768                                                 .addr = addrs[i].addr,
769                                                 .preferred = htonl(prefix_pref),
770                                                 .valid = htonl(prefix_valid)
771                                         };
772                                         n.addr.s6_addr32[3] = htonl(a->assigned);
773                                         size_t entrlen = sizeof(n) - 4;
774
775                                         if (iface->managed < RELAYD_MANAGED_NO_AFLAG && i != m &&
776                                                         addrs[i].prefix == 64)
777                                                 continue;
778
779                                         if (datalen + entrlen + 4 > buflen || a->assigned == 0)
780                                                 continue;
781
782                                         memcpy(buf + datalen, &n, sizeof(n));
783                                         datalen += entrlen + 4;
784                                 }
785
786                                 // Calculate T1 / T2 based on non-deprecated addresses
787                                 if (prefix_pref > 0) {
788                                         if (prefix_pref < pref)
789                                                 pref = prefix_pref;
790
791                                         if (prefix_valid < valid)
792                                                 valid = prefix_valid;
793                                 }
794                         }
795
796                         a->valid_until = valid + now;
797                         out.t1 = htonl(pref * 5 / 10);
798                         out.t2 = htonl(pref * 8 / 10);
799
800                         if (!out.t1)
801                                 out.t1 = htonl(1);
802
803                         if (!out.t2)
804                                 out.t2 = htonl(1);
805                 }
806
807                 if (!request) {
808                         uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
809                         uint16_t otype, olen;
810                         dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
811                                 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&odata[-4];
812                                 struct dhcpv6_ia_addr *n = (struct dhcpv6_ia_addr*)&odata[-4];
813                                 if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*p) - 4) &&
814                                                 (otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*n) - 4))
815                                         continue;
816
817                                 bool found = false;
818                                 if (a) {
819                                         struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
820                                         size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
821
822                                         for (size_t i = 0; i < addrlen; ++i) {
823                                                 if (addrs[i].prefix > 96 ||
824                                                                 addrs[i].preferred <= (uint32_t)now)
825                                                         continue;
826
827                                                 struct in6_addr addr = addrs[i].addr;
828                                                 if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
829                                                         addr.s6_addr32[1] |= htonl(a->assigned);
830
831                                                         if (!memcmp(&p->addr, &addr, sizeof(addr)) &&
832                                                                         p->prefix == ((a->managed) ? addrs[i].prefix : a->length))
833                                                                 found = true;
834                                                 } else {
835                                                         addr.s6_addr32[3] = htonl(a->assigned);
836
837                                                         if (!memcmp(&n->addr, &addr, sizeof(addr)))
838                                                                 found = true;
839                                                 }
840                                         }
841                                 }
842
843                                 if (!found) {
844                                         if (otype == DHCPV6_OPT_IA_PREFIX) {
845                                                 struct dhcpv6_ia_prefix inv = {
846                                                         .type = htons(DHCPV6_OPT_IA_PREFIX),
847                                                         .len = htons(sizeof(inv) - 4),
848                                                         .preferred = 0,
849                                                         .valid = 0,
850                                                         .prefix = p->prefix,
851                                                         .addr = p->addr
852                                                 };
853
854                                                 if (datalen + sizeof(inv) > buflen)
855                                                         continue;
856
857                                                 memcpy(buf + datalen, &inv, sizeof(inv));
858                                                 datalen += sizeof(inv);
859                                         } else {
860                                                 struct dhcpv6_ia_addr inv = {
861                                                         .type = htons(DHCPV6_OPT_IA_ADDR),
862                                                         .len = htons(sizeof(inv) - 4),
863                                                         .addr = n->addr,
864                                                         .preferred = 0,
865                                                         .valid = 0
866                                                 };
867
868                                                 if (datalen + sizeof(inv) > buflen)
869                                                         continue;
870
871                                                 memcpy(buf + datalen, &inv, sizeof(inv));
872                                                 datalen += sizeof(inv);
873                                         }
874                                 }
875                         }
876                 }
877         }
878
879         out.len = htons(datalen - 4);
880         memcpy(buf, &out, sizeof(out));
881         return datalen;
882 }
883
884
885 static void dhcpv6_log(uint8_t msgtype, struct interface *iface, time_t now,
886                 const char *duidbuf, bool is_pd, struct dhcpv6_assignment *a, int code)
887 {
888         const char *type = "UNKNOWN";
889         const char *status = "UNKNOWN";
890
891         if (msgtype == DHCPV6_MSG_RENEW)
892                 return;
893
894         switch (msgtype) {
895         case DHCPV6_MSG_SOLICIT:
896                 type = "SOLICIT";
897                 break;
898         case DHCPV6_MSG_REQUEST:
899                 type = "REQUEST";
900                 break;
901         case DHCPV6_MSG_CONFIRM:
902                 type = "CONFIRM";
903                 break;
904         case DHCPV6_MSG_RENEW:
905                 type = "RENEW";
906                 break;
907         case DHCPV6_MSG_REBIND:
908                 type = "REBIND";
909                 break;
910         case DHCPV6_MSG_RELEASE:
911                 type = "RELEASE";
912                 break;
913         case DHCPV6_MSG_DECLINE:
914                 type = "DECLINE";
915                 break;
916         }
917
918         switch (code) {
919         case DHCPV6_STATUS_OK:
920                 status = "ok";
921                 break;
922         case DHCPV6_STATUS_NOADDRSAVAIL:
923                 status = "no addresses available";
924                 break;
925         case DHCPV6_STATUS_NOBINDING:
926                 status = "no binding";
927                 break;
928         case DHCPV6_STATUS_NOTONLINK:
929                 status = "not on-link";
930                 break;
931         case DHCPV6_STATUS_NOPREFIXAVAIL:
932                 status = "no prefix available";
933                 break;
934         }
935
936         char leasebuf[256] = "";
937
938         if (a) {
939                 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
940                 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
941                 size_t lbsize = 0;
942                 char addrbuf[INET6_ADDRSTRLEN];
943
944                 for (size_t i = 0; i < addrlen; ++i) {
945                         if (addrs[i].prefix > 96 || addrs[i].preferred <= (uint32_t)now)
946                                 continue;
947
948                         struct in6_addr addr = addrs[i].addr;
949                         int prefix = a->managed ? addrs[i].prefix : a->length;
950                         if (prefix == 128)
951                                 addr.s6_addr32[3] = htonl(a->assigned);
952                         else
953                                 addr.s6_addr32[1] |= htonl(a->assigned);
954
955                         inet_ntop(AF_INET6, &addr, addrbuf, sizeof(addrbuf));
956                         lbsize += snprintf(leasebuf + lbsize, sizeof(leasebuf) - lbsize, "%s/%d ", addrbuf, prefix);
957                 }
958         }
959
960         syslog(LOG_WARNING, "DHCPV6 %s %s from %s on %s: %s %s", type, (is_pd) ? "IA_PD" : "IA_NA",
961                         duidbuf, iface->ifname, status, leasebuf);
962 }
963
964
965
966 ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
967                 const struct sockaddr_in6 *addr, const void *data, const uint8_t *end)
968 {
969         time_t now = odhcpd_time();
970         size_t response_len = 0;
971         const struct dhcpv6_client_header *hdr = data;
972         uint8_t *start = (uint8_t*)&hdr[1], *odata;
973         uint16_t otype, olen;
974
975         // Find and parse client-id and hostname
976         bool accept_reconf = false;
977         uint8_t *clid_data = NULL, clid_len = 0, mac[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
978         char hostname[256];
979         size_t hostname_len = 0;
980         bool notonlink = false;
981         char duidbuf[261];
982
983         dhcpv6_for_each_option(start, end, otype, olen, odata) {
984                 if (otype == DHCPV6_OPT_CLIENTID) {
985                         clid_data = odata;
986                         clid_len = olen;
987
988                         if (olen == 14 && odata[0] == 0 && odata[1] == 1)
989                                 memcpy(mac, &odata[8], sizeof(mac));
990                         else if (olen == 10 && odata[0] == 0 && odata[1] == 3)
991                                 memcpy(mac, &odata[4], sizeof(mac));
992
993                         if (olen <= 130)
994                                 odhcpd_hexlify(duidbuf, odata, olen);
995                 } else if (otype == DHCPV6_OPT_FQDN && olen >= 2 && olen <= 255) {
996                         uint8_t fqdn_buf[256];
997                         memcpy(fqdn_buf, odata, olen);
998                         fqdn_buf[olen++] = 0;
999
1000                         if (dn_expand(&fqdn_buf[1], &fqdn_buf[olen], &fqdn_buf[1], hostname, sizeof(hostname)) > 0)
1001                                 hostname_len = strcspn(hostname, ".");
1002                 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
1003                         accept_reconf = true;
1004                 }
1005         }
1006
1007         if (!clid_data || !clid_len || clid_len > 130)
1008                 goto out;
1009
1010         update(iface);
1011
1012         struct dhcpv6_assignment *first = NULL;
1013         dhcpv6_for_each_option(start, end, otype, olen, odata) {
1014                 bool is_pd = (otype == DHCPV6_OPT_IA_PD);
1015                 bool is_na = (otype == DHCPV6_OPT_IA_NA);
1016                 bool ia_addr_present = false;
1017                 if (!is_pd && !is_na)
1018                         continue;
1019
1020                 struct dhcpv6_ia_hdr *ia = (struct dhcpv6_ia_hdr*)&odata[-4];
1021                 size_t ia_response_len = 0;
1022                 uint8_t reqlen = (is_pd) ? 62 : 128;
1023                 uint32_t reqhint = 0;
1024
1025                 // Parse request hint for IA-PD
1026                 if (is_pd) {
1027                         uint8_t *sdata;
1028                         uint16_t stype, slen;
1029                         dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1030                                 if (stype != DHCPV6_OPT_IA_PREFIX || slen < sizeof(struct dhcpv6_ia_prefix) - 4)
1031                                         continue;
1032
1033                                 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&sdata[-4];
1034                                 if (p->prefix) {
1035                                         reqlen = p->prefix;
1036                                         reqhint = ntohl(p->addr.s6_addr32[1]);
1037                                         if (reqlen > 32 && reqlen <= 64)
1038                                                 reqhint &= (1U << (64 - reqlen)) - 1;
1039                                 }
1040                         }
1041
1042                         if (reqlen > 64)
1043                                 reqlen = 64;
1044                 } else if (is_na) {
1045                         uint8_t *sdata;
1046                         uint16_t stype, slen;
1047                         dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1048                                 if (stype != DHCPV6_OPT_IA_ADDR || slen < sizeof(struct dhcpv6_ia_addr) - 4)
1049                                         continue;
1050
1051                                 ia_addr_present = true;
1052                         }
1053                 }
1054
1055                 // Find assignment
1056                 struct dhcpv6_assignment *c, *a = NULL;
1057                 list_for_each_entry(c, &iface->ia_assignments, head) {
1058                         if (((c->clid_len == clid_len && !memcmp(c->clid_data, clid_data, clid_len)) ||
1059                                         (c->clid_len >= clid_len && !c->clid_data[0] && !c->clid_data[1]
1060                                                 && !memcmp(c->mac, mac, sizeof(mac)))) &&
1061                                         (c->iaid == ia->iaid || c->valid_until < now) &&
1062                                         ((is_pd && c->length <= 64) || (is_na && c->length == 128))) {
1063                                 a = c;
1064
1065                                 // Reset state
1066                                 apply_lease(iface, a, false);
1067                                 memcpy(a->clid_data, clid_data, clid_len);
1068                                 a->clid_len = clid_len;
1069                                 a->iaid = ia->iaid;
1070                                 a->peer = *addr;
1071                                 a->reconf_cnt = 0;
1072                                 a->reconf_sent = 0;
1073                                 break;
1074                         }
1075                 }
1076
1077                 // Generic message handling
1078                 uint16_t status = DHCPV6_STATUS_OK;
1079                 if (a && a->managed_size < 0) {
1080                         return -1;
1081                 } else if (hdr->msg_type == DHCPV6_MSG_SOLICIT || hdr->msg_type == DHCPV6_MSG_REQUEST) {
1082                         bool assigned = !!a;
1083
1084                         if (!a && !iface->no_dynamic_dhcp) { // Create new binding
1085                                 a = calloc(1, sizeof(*a) + clid_len);
1086                                 if (a) {
1087                                         a->clid_len = clid_len;
1088                                         a->iaid = ia->iaid;
1089                                         a->length = reqlen;
1090                                         a->peer = *addr;
1091                                         a->assigned = reqhint;
1092
1093                                         if (first)
1094                                                 memcpy(a->key, first->key, sizeof(a->key));
1095                                         else
1096                                                 odhcpd_urandom(a->key, sizeof(a->key));
1097                                         memcpy(a->clid_data, clid_data, clid_len);
1098
1099                                         if (is_pd)
1100                                                 while (!(assigned = assign_pd(iface, a)) &&
1101                                                                 !a->managed_size && ++a->length <= 64);
1102                                         else
1103                                                 assigned = assign_na(iface, a);
1104
1105                                         if (a->managed_size && !assigned)
1106                                                 return -1;
1107                                 }
1108                         }
1109
1110                         if (!assigned || iface->ia_addr_len == 0) { // Set error status
1111                                 status = (is_pd) ? DHCPV6_STATUS_NOPREFIXAVAIL : DHCPV6_STATUS_NOADDRSAVAIL;
1112                         } else if (assigned && !first) { //
1113                                 size_t handshake_len = 4;
1114                                 buf[0] = 0;
1115                                 buf[1] = DHCPV6_OPT_RECONF_ACCEPT;
1116                                 buf[2] = 0;
1117                                 buf[3] = 0;
1118
1119                                 if (hdr->msg_type == DHCPV6_MSG_REQUEST) {
1120                                         struct dhcpv6_auth_reconfigure auth = {
1121                                                 htons(DHCPV6_OPT_AUTH),
1122                                                 htons(sizeof(auth) - 4),
1123                                                 3, 1, 0,
1124                                                 {htonl(time(NULL)), htonl(++serial)},
1125                                                 1,
1126                                                 {0}
1127                                         };
1128                                         memcpy(auth.key, a->key, sizeof(a->key));
1129                                         memcpy(buf + handshake_len, &auth, sizeof(auth));
1130                                         handshake_len += sizeof(auth);
1131                                 }
1132
1133                                 buf += handshake_len;
1134                                 buflen -= handshake_len;
1135                                 response_len += handshake_len;
1136
1137                                 first = a;
1138                         }
1139
1140                         ia_response_len = append_reply(buf, buflen, status, ia, a, iface, true);
1141
1142                         // Was only a solicitation: mark binding for removal
1143                         if (assigned && hdr->msg_type == DHCPV6_MSG_SOLICIT) {
1144                                 a->valid_until = 0;
1145                         } else if (assigned && hdr->msg_type == DHCPV6_MSG_REQUEST) {
1146                                 if (hostname_len > 0) {
1147                                         a->hostname = realloc(a->hostname, hostname_len + 1);
1148                                         if (a->hostname) {
1149                                                 memcpy(a->hostname, hostname, hostname_len);
1150                                                 a->hostname[hostname_len] = 0;
1151                                         }
1152                                 }
1153                                 a->accept_reconf = accept_reconf;
1154                                 apply_lease(iface, a, true);
1155                         } else if (!assigned && a && a->managed_size == 0) { // Cleanup failed assignment
1156                                 free_dhcpv6_assignment(a);
1157                         }
1158                 } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1159                                 hdr->msg_type == DHCPV6_MSG_RELEASE ||
1160                                 hdr->msg_type == DHCPV6_MSG_REBIND ||
1161                                 hdr->msg_type == DHCPV6_MSG_DECLINE) {
1162                         if (!a && hdr->msg_type != DHCPV6_MSG_REBIND) {
1163                                 status = DHCPV6_STATUS_NOBINDING;
1164                                 ia_response_len = append_reply(buf, buflen, status, ia, a, iface, false);
1165                         } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1166                                         hdr->msg_type == DHCPV6_MSG_REBIND) {
1167                                 ia_response_len = append_reply(buf, buflen, status, ia, a, iface, false);
1168                                 if (a)
1169                                         apply_lease(iface, a, true);
1170                         } else if (hdr->msg_type == DHCPV6_MSG_RELEASE) {
1171                                 a->valid_until = 0;
1172                                 apply_lease(iface, a, false);
1173                         } else if (hdr->msg_type == DHCPV6_MSG_DECLINE && a->length == 128) {
1174                                 a->clid_len = 0;
1175                                 a->valid_until = now + 3600; // Block address for 1h
1176                         }
1177                 } else if (hdr->msg_type == DHCPV6_MSG_CONFIRM && ia_addr_present) {
1178                         // Send NOTONLINK for CONFIRM with addr present so that clients restart connection
1179                         status = DHCPV6_STATUS_NOTONLINK;
1180                         ia_response_len = append_reply(buf, buflen, status, ia, a, iface, true);
1181                         notonlink = true;
1182                 }
1183
1184                 buf += ia_response_len;
1185                 buflen -= ia_response_len;
1186                 response_len += ia_response_len;
1187                 dhcpv6_log(hdr->msg_type, iface, now, duidbuf, is_pd, a, status);
1188         }
1189
1190         if ((hdr->msg_type == DHCPV6_MSG_RELEASE || hdr->msg_type == DHCPV6_MSG_DECLINE || notonlink) &&
1191                         response_len + 6 < buflen) {
1192                 buf[0] = 0;
1193                 buf[1] = DHCPV6_OPT_STATUS;
1194                 buf[2] = 0;
1195                 buf[3] = 2;
1196                 buf[4] = 0;
1197                 buf[5] = (notonlink) ? DHCPV6_STATUS_NOTONLINK : DHCPV6_STATUS_OK;
1198                 response_len += 6;
1199         }
1200
1201         dhcpv6_write_statefile();
1202
1203 out:
1204         return response_len;
1205 }