9b03227e0482352476ba497f7f4fabb4bc90033c
[odhcp6c.git] / src / dhcpv6.c
1 /**
2  * Copyright (C) 2012-2013 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 <time.h>
16 #include <fcntl.h>
17 #include <errno.h>
18 #include <stdlib.h>
19 #include <signal.h>
20 #include <limits.h>
21 #include <resolv.h>
22 #include <string.h>
23 #include <unistd.h>
24 #include <syslog.h>
25 #include <stdbool.h>
26 #include <sys/time.h>
27 #include <sys/ioctl.h>
28 #include <sys/socket.h>
29 #include <netinet/in.h>
30
31 #include <net/if.h>
32 #include <net/ethernet.h>
33
34 #include "odhcp6c.h"
35 #include "md5.h"
36
37
38 #define ALL_DHCPV6_RELAYS {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
39                 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x02}}}
40 #define DHCPV6_CLIENT_PORT 546
41 #define DHCPV6_SERVER_PORT 547
42 #define DHCPV6_DUID_LLADDR 3
43 #define DHCPV6_REQ_DELAY 1
44
45
46 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
47                 const uint8_t transaction[3], enum dhcpv6_msg type,
48                 const struct in6_addr *daddr);
49
50 static int dhcpv6_parse_ia(void *opt, void *end);
51
52 static int dhcpv6_calc_refresh_timers(void);
53 static void dhcpv6_handle_status_code(_unused const enum dhcpv6_msg orig,
54                 const uint16_t code, const void *status_msg, const int len,
55                 int *ret);
56 static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig,
57                 const struct dhcpv6_ia_hdr *ia_hdr, const uint16_t code,
58                 const void *status_msg, const int len,
59                 bool handled_status_codes[_DHCPV6_Status_Max],
60                 int *ret);
61
62 static reply_handler dhcpv6_handle_reply;
63 static reply_handler dhcpv6_handle_advert;
64 static reply_handler dhcpv6_handle_rebind_reply;
65 static reply_handler dhcpv6_handle_reconfigure;
66 static int dhcpv6_commit_advert(void);
67
68
69
70 // RFC 3315 - 5.5 Timeout and Delay values
71 static struct dhcpv6_retx dhcpv6_retx[_DHCPV6_MSG_MAX] = {
72         [DHCPV6_MSG_UNKNOWN] = {false, 1, 120, 0, "<POLL>",
73                         dhcpv6_handle_reconfigure, NULL},
74         [DHCPV6_MSG_SOLICIT] = {true, 1, 3600, 0, "SOLICIT",
75                         dhcpv6_handle_advert, dhcpv6_commit_advert},
76         [DHCPV6_MSG_REQUEST] = {true, 1, 30, 10, "REQUEST",
77                         dhcpv6_handle_reply, NULL},
78         [DHCPV6_MSG_RENEW] = {false, 10, 600, 0, "RENEW",
79                         dhcpv6_handle_reply, NULL},
80         [DHCPV6_MSG_REBIND] = {false, 10, 600, 0, "REBIND",
81                         dhcpv6_handle_rebind_reply, NULL},
82         [DHCPV6_MSG_RELEASE] = {false, 1, 0, 5, "RELEASE", NULL, NULL},
83         [DHCPV6_MSG_DECLINE] = {false, 1, 0, 5, "DECLINE", NULL, NULL},
84         [DHCPV6_MSG_INFO_REQ] = {true, 1, 120, 0, "INFOREQ",
85                         dhcpv6_handle_reply, NULL},
86 };
87
88
89 // Sockets
90 static int sock = -1;
91 static int ifindex = -1;
92 static int64_t t1 = 0, t2 = 0, t3 = 0;
93
94 // IA states
95 static int request_prefix = -1;
96 static enum odhcp6c_ia_mode na_mode = IA_MODE_NONE, pd_mode = IA_MODE_NONE;
97 static bool accept_reconfig = false;
98
99 // Reconfigure key
100 static uint8_t reconf_key[16];
101
102
103 int init_dhcpv6(const char *ifname, int request_pd, int sol_timeout)
104 {
105         request_prefix = request_pd;
106         dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = sol_timeout;
107
108         sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
109         if (sock < 0)
110                 return -1;
111
112         // Detect interface
113         struct ifreq ifr;
114         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
115         if (ioctl(sock, SIOCGIFINDEX, &ifr) < 0)
116                 return -1;
117         ifindex = ifr.ifr_ifindex;
118
119         // Create client DUID
120         size_t client_id_len;
121         odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
122         if (client_id_len == 0) {
123                 uint8_t duid[14] = {0, DHCPV6_OPT_CLIENTID, 0, 10, 0,
124                                 DHCPV6_DUID_LLADDR, 0, 1};
125
126                 if (ioctl(sock, SIOCGIFHWADDR, &ifr) >= 0)
127                         memcpy(&duid[8], ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
128
129                 uint8_t zero[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
130                 struct ifreq ifs[100], *ifp, *ifend;
131                 struct ifconf ifc;
132                 ifc.ifc_req = ifs;
133                 ifc.ifc_len = sizeof(ifs);
134
135                 if (!memcmp(&duid[8], zero, ETHER_ADDR_LEN) &&
136                                 ioctl(sock, SIOCGIFCONF, &ifc) >= 0) {
137                         // If our interface doesn't have an address...
138                         ifend = ifs + (ifc.ifc_len / sizeof(struct ifreq));
139                         for (ifp = ifc.ifc_req; ifp < ifend &&
140                                         !memcmp(&duid[8], zero, ETHER_ADDR_LEN); ifp++) {
141                                 memcpy(ifr.ifr_name, ifp->ifr_name,
142                                                 sizeof(ifr.ifr_name));
143                                 if (ioctl(sock, SIOCGIFHWADDR, &ifr) < 0)
144                                         continue;
145                                 memcpy(&duid[8], ifr.ifr_hwaddr.sa_data,
146                                                 ETHER_ADDR_LEN);
147                         }
148                 }
149
150                 odhcp6c_add_state(STATE_CLIENT_ID, duid, sizeof(duid));
151         }
152
153         // Create ORO
154         uint16_t oro[] = {
155                         htons(DHCPV6_OPT_SIP_SERVER_D),
156                         htons(DHCPV6_OPT_SIP_SERVER_A),
157                         htons(DHCPV6_OPT_DNS_SERVERS),
158                         htons(DHCPV6_OPT_DNS_DOMAIN),
159                         htons(DHCPV6_OPT_NTP_SERVER),
160                         htons(DHCPV6_OPT_AFTR_NAME),
161                         htons(DHCPV6_OPT_PD_EXCLUDE),
162 #ifdef EXT_PREFIX_CLASS
163                         htons(DHCPV6_OPT_PREFIX_CLASS),
164 #endif
165         };
166         odhcp6c_add_state(STATE_ORO, oro, sizeof(oro));
167
168         do {
169                 // Configure IPv6-options
170                 int val = 1;
171                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val)) < 0)
172                         break;
173                 if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) < 0)
174                         break;
175                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val, sizeof(val)) < 0)
176                         break;
177
178                 val = 0;
179                 if (setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &val, sizeof(val)) < 0)
180                         break;
181                 if (setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname)) < 0)
182                         break;
183
184                 struct sockaddr_in6 client_addr = { .sin6_family = AF_INET6,
185                         .sin6_port = htons(DHCPV6_CLIENT_PORT), .sin6_flowinfo = 0 };
186                 if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr)) < 0)
187                         break;
188
189                 return 0;
190         } while (0);
191
192         return -1;
193 }
194
195
196 void dhcpv6_set_ia_mode(enum odhcp6c_ia_mode na, enum odhcp6c_ia_mode pd)
197 {
198         na_mode = na;
199         pd_mode = pd;
200 }
201
202
203 static void dhcpv6_send(enum dhcpv6_msg type, uint8_t trid[3], uint32_t ecs)
204 {
205         // Build FQDN
206         char fqdn_buf[256];
207         gethostname(fqdn_buf, sizeof(fqdn_buf));
208         struct {
209                 uint16_t type;
210                 uint16_t len;
211                 uint8_t flags;
212                 uint8_t data[256];
213         } fqdn;
214         size_t fqdn_len = 5 + dn_comp(fqdn_buf, fqdn.data,
215                         sizeof(fqdn.data), NULL, NULL);
216         fqdn.type = htons(DHCPV6_OPT_FQDN);
217         fqdn.len = htons(fqdn_len - 4);
218         fqdn.flags = 0;
219
220
221         // Build Client ID
222         size_t cl_id_len;
223         void *cl_id = odhcp6c_get_state(STATE_CLIENT_ID, &cl_id_len);
224
225         // Get Server ID
226         size_t srv_id_len;
227         void *srv_id = odhcp6c_get_state(STATE_SERVER_ID, &srv_id_len);
228
229         // Build IA_PDs
230         size_t ia_pd_entries, ia_pd_len = 0;
231         struct odhcp6c_entry *e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
232         ia_pd_entries /= sizeof(*e);
233         struct dhcpv6_ia_hdr hdr_ia_pd = {
234                 htons(DHCPV6_OPT_IA_PD),
235                 htons(sizeof(hdr_ia_pd) - 4),
236                 1, 0, 0
237         };
238
239
240         uint8_t *ia_pd = alloca(ia_pd_entries * (sizeof(struct dhcpv6_ia_prefix) + 10));
241         for (size_t i = 0; i < ia_pd_entries; ++i) {
242                 uint8_t ex_len = 0;
243                 if (e[i].priority > 0)
244                         ex_len = ((e[i].priority - e[i].length - 1) / 8) + 6;
245
246                 struct dhcpv6_ia_prefix p = {
247                         .type = htons(DHCPV6_OPT_IA_PREFIX),
248                         .len = htons(sizeof(p) - 4U + ex_len),
249                         .prefix = e[i].length,
250                         .addr = e[i].target
251                 };
252
253                 memcpy(ia_pd + ia_pd_len, &p, sizeof(p));
254                 ia_pd_len += sizeof(p);
255
256                 if (ex_len) {
257                         ia_pd[ia_pd_len++] = 0;
258                         ia_pd[ia_pd_len++] = DHCPV6_OPT_PD_EXCLUDE;
259                         ia_pd[ia_pd_len++] = 0;
260                         ia_pd[ia_pd_len++] = ex_len - 4;
261                         ia_pd[ia_pd_len++] = e[i].priority;
262
263                         uint32_t excl = ntohl(e[i].router.s6_addr32[1]);
264                         excl >>= (64 - e[i].priority);
265                         excl <<= 8 - ((e[i].priority - e[i].length) % 8);
266
267                         for (size_t i = ex_len - 5; i > 0; --i, excl >>= 8)
268                                 ia_pd[ia_pd_len + i] = excl & 0xff;
269                         ia_pd_len += ex_len - 5;
270                 }
271         }
272
273         struct dhcpv6_ia_prefix pref = {
274                 .type = htons(DHCPV6_OPT_IA_PREFIX),
275                 .len = htons(25), .prefix = request_prefix
276         };
277         if (request_prefix > 0 && ia_pd_len == 0 && type == DHCPV6_MSG_SOLICIT) {
278                 ia_pd = (uint8_t*)&pref;
279                 ia_pd_len = sizeof(pref);
280         }
281         hdr_ia_pd.len = htons(ntohs(hdr_ia_pd.len) + ia_pd_len);
282
283         // Build IA_NAs
284         size_t ia_na_entries, ia_na_len = 0;
285         void *ia_na = NULL;
286         e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
287         ia_na_entries /= sizeof(*e);
288
289         struct dhcpv6_ia_hdr hdr_ia_na = {
290                 htons(DHCPV6_OPT_IA_NA),
291                 htons(sizeof(hdr_ia_na) - 4),
292                 1, 0, 0
293         };
294
295         struct dhcpv6_ia_addr pa[ia_na_entries];
296         for (size_t i = 0; i < ia_na_entries; ++i) {
297                 pa[i].type = htons(DHCPV6_OPT_IA_ADDR);
298                 pa[i].len = htons(sizeof(pa[i]) - 4U);
299                 pa[i].addr = e[i].target;
300                 pa[i].preferred = 0;
301                 pa[i].valid = 0;
302         }
303
304         ia_na = pa;
305         ia_na_len = sizeof(pa);
306         hdr_ia_na.len = htons(ntohs(hdr_ia_na.len) + ia_na_len);
307
308         // Reconfigure Accept
309         struct {
310                 uint16_t type;
311                 uint16_t length;
312         } reconf_accept = {htons(DHCPV6_OPT_RECONF_ACCEPT), 0};
313
314         // Request Information Refresh
315         uint16_t oro_refresh = htons(DHCPV6_OPT_INFO_REFRESH);
316
317         // Prepare Header
318         size_t oro_len;
319         void *oro = odhcp6c_get_state(STATE_ORO, &oro_len);
320         struct {
321                 uint8_t type;
322                 uint8_t trid[3];
323                 uint16_t elapsed_type;
324                 uint16_t elapsed_len;
325                 uint16_t elapsed_value;
326                 uint16_t oro_type;
327                 uint16_t oro_len;
328         } hdr = {
329                 type, {trid[0], trid[1], trid[2]},
330                 htons(DHCPV6_OPT_ELAPSED), htons(2),
331                         htons((ecs > 0xffff) ? 0xffff : ecs),
332                 htons(DHCPV6_OPT_ORO), htons(oro_len),
333         };
334
335         struct iovec iov[] = {
336                 {&hdr, sizeof(hdr)},
337                 {oro, oro_len},
338                 {&oro_refresh, 0},
339                 {cl_id, cl_id_len},
340                 {srv_id, srv_id_len},
341                 {&reconf_accept, sizeof(reconf_accept)},
342                 {&fqdn, fqdn_len},
343                 {&hdr_ia_na, sizeof(hdr_ia_na)},
344                 {ia_na, ia_na_len},
345                 {&hdr_ia_pd, sizeof(hdr_ia_pd)},
346                 {ia_pd, ia_pd_len},
347         };
348
349         size_t cnt = ARRAY_SIZE(iov);
350         if (type == DHCPV6_MSG_INFO_REQ) {
351                 cnt = 5;
352                 iov[2].iov_len = sizeof(oro_refresh);
353                 hdr.oro_len = htons(oro_len + sizeof(oro_refresh));
354         } else if (!request_prefix) {
355                 cnt = 9;
356         }
357
358         // Disable IAs if not used
359         if (type != DHCPV6_MSG_SOLICIT) {
360                 iov[5].iov_len = 0;
361                 if (ia_na_len == 0)
362                         iov[7].iov_len = 0;
363                 if (ia_pd_len == 0)
364                         iov[9].iov_len = 0;
365         }
366
367         if (na_mode == IA_MODE_NONE)
368                 iov[7].iov_len = 0;
369
370         struct sockaddr_in6 srv = {AF_INET6, htons(DHCPV6_SERVER_PORT),
371                 0, ALL_DHCPV6_RELAYS, ifindex};
372         struct msghdr msg = {&srv, sizeof(srv), iov, cnt, NULL, 0, 0};
373
374         sendmsg(sock, &msg, 0);
375 }
376
377
378 static int64_t dhcpv6_rand_delay(int64_t time)
379 {
380         int random;
381         odhcp6c_random(&random, sizeof(random));
382         return (time * ((int64_t)random % 1000LL)) / 10000LL;
383 }
384
385
386 int dhcpv6_request(enum dhcpv6_msg type)
387 {
388         uint8_t rc = 0;
389         uint64_t timeout = UINT32_MAX;
390         struct dhcpv6_retx *retx = &dhcpv6_retx[type];
391
392         if (retx->delay) {
393                 struct timespec ts = {0, 0};
394                 ts.tv_nsec = dhcpv6_rand_delay(10 * DHCPV6_REQ_DELAY);
395                 nanosleep(&ts, NULL);
396         }
397
398         if (type == DHCPV6_MSG_UNKNOWN)
399                 timeout = t1;
400         else if (type == DHCPV6_MSG_RENEW)
401                 timeout = (t2 > t1) ? t2 - t1 : 0;
402         else if (type == DHCPV6_MSG_REBIND)
403                 timeout = (t3 > t2) ? t3 - t2 : 0;
404
405         if (timeout == 0)
406                 return -1;
407
408         syslog(LOG_NOTICE, "Starting %s transaction (timeout %llus, max rc %d)",
409                         retx->name, (unsigned long long)timeout, retx->max_rc);
410
411         uint64_t start = odhcp6c_get_milli_time(), round_start = start, elapsed;
412
413         // Generate transaction ID
414         uint8_t trid[3] = {0, 0, 0};
415         if (type != DHCPV6_MSG_UNKNOWN)
416                 odhcp6c_random(trid, sizeof(trid));
417         ssize_t len = -1;
418         int64_t rto = 0;
419
420         do {
421                 if (rto == 0) {
422                         int64_t delay = dhcpv6_rand_delay(retx->init_timeo * 1000);
423
424                         // First RT MUST be strictly greater than IRT for solicit messages (RFC3313 17.1.2)
425                         while (type == DHCPV6_MSG_SOLICIT && delay <= 0)
426                                 delay = dhcpv6_rand_delay(retx->init_timeo * 1000);
427
428                         rto = (retx->init_timeo * 1000 + delay);
429                 }
430                 else
431                         rto = (2 * rto + dhcpv6_rand_delay(rto));
432
433                 if (retx->max_timeo && (rto >= retx->max_timeo * 1000))
434                         rto = retx->max_timeo * 1000 +
435                                 dhcpv6_rand_delay(retx->max_timeo * 1000);
436
437                 // Calculate end for this round and elapsed time
438                 uint64_t round_end = round_start + rto;
439                 elapsed = round_start - start;
440
441                 // Don't wait too long
442                 if (round_end - start > timeout * 1000)
443                         round_end = timeout * 1000 + start;
444
445                 // Built and send package
446                 if (type != DHCPV6_MSG_UNKNOWN) {
447                         if (type != DHCPV6_MSG_SOLICIT)
448                                 syslog(LOG_NOTICE, "Send %s message (elapsed %llums, rc %d)",
449                                                 retx->name, (unsigned long long)elapsed, rc);
450                         dhcpv6_send(type, trid, elapsed / 10);
451                         rc++;
452                 }
453
454                 // Receive rounds
455                 for (; len < 0 && round_start < round_end;
456                                 round_start = odhcp6c_get_milli_time()) {
457                         uint8_t buf[1536], cmsg_buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
458                         struct iovec iov = {buf, sizeof(buf)};
459                         struct msghdr msg = {NULL, 0, &iov, 1,
460                                         cmsg_buf, sizeof(cmsg_buf), 0};
461                         struct in6_pktinfo *pktinfo = NULL;
462
463                         // Check for pending signal
464                         if (odhcp6c_signal_process())
465                                 return -1;
466
467                         // Set timeout for receiving
468                         uint64_t t = round_end - round_start;
469                         struct timeval timeout = {t / 1000, (t % 1000) * 1000};
470                         setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO,
471                                         &timeout, sizeof(timeout));
472
473                         // Receive cycle
474                         len = recvmsg(sock, &msg, 0);
475                         if (len < 0)
476                                 continue;
477
478                         for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL;
479                                 ch = CMSG_NXTHDR(&msg, ch)) {
480                                 if (ch->cmsg_level == SOL_IPV6 &&
481                                         ch->cmsg_type == IPV6_PKTINFO) {
482                                         pktinfo = (struct in6_pktinfo *)CMSG_DATA(ch);
483                                         break;
484                                 }
485                         }
486
487                         if (pktinfo == NULL) {
488                                 len = -1;
489                                 continue;
490                         }
491
492                         if (!dhcpv6_response_is_valid(buf, len, trid,
493                                                         type, &pktinfo->ipi6_addr)) {
494                                 len = -1;
495                                 continue;
496                         }
497
498                         uint8_t *opt = &buf[4];
499                         uint8_t *opt_end = opt + len - 4;
500
501                         round_start = odhcp6c_get_milli_time();
502                         elapsed = round_start - start;
503                         syslog(LOG_NOTICE, "Got a valid reply after "
504                                         "%llums", (unsigned long long)elapsed);
505
506                         if (retx->handler_reply)
507                                 len = retx->handler_reply(type, rc, opt, opt_end);
508
509                         if (len > 0 && round_end - round_start > 1000)
510                                 round_end = 1000 + round_start;
511                 }
512
513                 // Allow
514                 if (retx->handler_finish)
515                         len = retx->handler_finish();
516         } while (len < 0 && ((elapsed / 1000 < timeout) && (!retx->max_rc || rc < retx->max_rc)));
517
518         return len;
519 }
520
521 // Message validation checks according to RFC3315 chapter 15
522 static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
523                 const uint8_t transaction[3], enum dhcpv6_msg type,
524                 const struct in6_addr *daddr)
525 {
526         const struct dhcpv6_header *rep = buf;
527         if (len < (ssize_t)sizeof(*rep) || memcmp(rep->tr_id,
528                         transaction, sizeof(rep->tr_id)))
529                 return false; // Invalid reply
530
531         if (type == DHCPV6_MSG_SOLICIT) {
532                 if (rep->msg_type != DHCPV6_MSG_ADVERT &&
533                                 rep->msg_type != DHCPV6_MSG_REPLY)
534                         return false;
535         } else if (type == DHCPV6_MSG_UNKNOWN) {
536                 if (!accept_reconfig || rep->msg_type != DHCPV6_MSG_RECONF)
537                         return false;
538         } else if (rep->msg_type != DHCPV6_MSG_REPLY) {
539                 return false;
540         }
541
542         uint8_t *end = ((uint8_t*)buf) + len, *odata,
543                 rcmsg = DHCPV6_MSG_UNKNOWN;
544         uint16_t otype, olen;
545         bool clientid_ok = false, serverid_ok = false, rcauth_ok = false,
546                 ia_present = false, options_valid = true;
547
548         size_t client_id_len, server_id_len;
549         void *client_id = odhcp6c_get_state(STATE_CLIENT_ID, &client_id_len);
550         void *server_id = odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
551
552         dhcpv6_for_each_option(&rep[1], end, otype, olen, odata) {
553                 if (otype == DHCPV6_OPT_CLIENTID) {
554                         clientid_ok = (olen + 4U == client_id_len) && !memcmp(
555                                         &odata[-4], client_id, client_id_len);
556                 } else if (otype == DHCPV6_OPT_SERVERID) {
557                         if (server_id_len)
558                                 serverid_ok = (olen + 4U == server_id_len) && !memcmp(
559                                                 &odata[-4], server_id, server_id_len);
560                         else
561                                 serverid_ok = true;
562                 } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
563                                 sizeof(struct dhcpv6_auth_reconfigure)) {
564                         struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
565                         if (r->protocol != 3 || r->algorithm != 1 || r->reconf_type != 2)
566                                 continue;
567
568                         md5_state_t md5;
569                         uint8_t serverhash[16], secretbytes[16], hash[16];
570                         memcpy(serverhash, r->key, sizeof(serverhash));
571                         memset(r->key, 0, sizeof(r->key));
572                         memcpy(secretbytes, reconf_key, sizeof(secretbytes));
573
574                         for (size_t i = 0; i < sizeof(secretbytes); ++i)
575                                 secretbytes[i] ^= 0x36;
576
577                         md5_init(&md5);
578                         md5_append(&md5, secretbytes, sizeof(secretbytes));
579                         md5_append(&md5, buf, len);
580                         md5_finish(&md5, hash);
581
582                         for (size_t i = 0; i < sizeof(secretbytes); ++i) {
583                                 secretbytes[i] ^= 0x36;
584                                 secretbytes[i] ^= 0x5c;
585                         }
586
587                         md5_init(&md5);
588                         md5_append(&md5, secretbytes, sizeof(secretbytes));
589                         md5_append(&md5, hash, 16);
590                         md5_finish(&md5, hash);
591
592                         rcauth_ok = !memcmp(hash, serverhash, sizeof(hash));
593                 } else if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1) {
594                         rcmsg = odata[0];
595                 } else if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)) {
596                         ia_present = true;
597                         if (olen < sizeof(struct dhcpv6_ia_hdr))
598                                 options_valid = false;
599                 }
600                 else if ((otype == DHCPV6_OPT_IA_ADDR) || (otype == DHCPV6_OPT_IA_PREFIX) ||
601                                 (otype == DHCPV6_OPT_PD_EXCLUDE)) {
602                         // Options are not allowed on global level
603                         options_valid = false;
604                 }
605         }
606
607         if (!options_valid)
608                 return false;
609
610         if (type == DHCPV6_MSG_INFO_REQ && ia_present)
611                 return false;
612
613         if (rep->msg_type == DHCPV6_MSG_RECONF) {
614                 if ((rcmsg != DHCPV6_MSG_RENEW && rcmsg != DHCPV6_MSG_INFO_REQ) ||
615                         (rcmsg == DHCPV6_MSG_INFO_REQ && ia_present) ||
616                         !rcauth_ok || IN6_IS_ADDR_MULTICAST(daddr))
617                         return false;
618         }
619
620         return clientid_ok && serverid_ok;
621 }
622
623
624 int dhcpv6_poll_reconfigure(void)
625 {
626         int ret = dhcpv6_request(DHCPV6_MSG_UNKNOWN);
627         if (ret != -1)
628                 ret = dhcpv6_request(ret);
629
630         return ret;
631 }
632
633
634 static int dhcpv6_handle_reconfigure(_unused enum dhcpv6_msg orig, const int rc,
635                 const void *opt, const void *end)
636 {
637         uint16_t otype, olen;
638         uint8_t *odata, msg = DHCPV6_MSG_RENEW;
639         dhcpv6_for_each_option(opt, end, otype, olen, odata)
640                 if (otype == DHCPV6_OPT_RECONF_MESSAGE && olen == 1 && (
641                                 odata[0] == DHCPV6_MSG_RENEW ||
642                                 odata[0] == DHCPV6_MSG_INFO_REQ))
643                         msg = odata[0];
644
645         dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN, rc, NULL, NULL);
646         return msg;
647 }
648
649
650 // Collect all advertised servers
651 static int dhcpv6_handle_advert(enum dhcpv6_msg orig, const int rc,
652                 const void *opt, const void *end)
653 {
654         uint16_t olen, otype;
655         uint8_t *odata, pref = 0;
656         struct dhcpv6_server_cand cand = {false, false, 0, 0, {0}, NULL, NULL, 0, 0};
657         bool have_na = false;
658         int have_pd = 0;
659
660         dhcpv6_for_each_option(opt, end, otype, olen, odata) {
661                 if (orig == DHCPV6_MSG_SOLICIT &&
662                                 (otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA) &&
663                                 olen > sizeof(struct dhcpv6_ia_hdr)) {
664                         struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
665                         dhcpv6_parse_ia(ia_hdr, odata + olen + sizeof(*ia_hdr));
666                 }
667
668                 if (otype == DHCPV6_OPT_SERVERID && olen <= 130) {
669                         memcpy(cand.duid, odata, olen);
670                         cand.duid_len = olen;
671                 } else if (otype == DHCPV6_OPT_STATUS && olen >= 2) {
672                         int error = ((int)odata[0] << 8 | (int)odata[1]);
673
674                         switch (error) {
675                         case DHCPV6_NoPrefixAvail:
676                                 // Status code on global level
677                                 if (pd_mode == IA_MODE_FORCE)
678                                         return -1;
679                                 cand.preference -= 2000;
680                                 break;
681
682                         case DHCPV6_NoAddrsAvail:
683                                 // Status code on global level
684                                 if (na_mode == IA_MODE_FORCE)
685                                         return -1;
686                                 break;
687
688                         default :
689                                 break;
690                         }
691                 } else if (otype == DHCPV6_OPT_PREF && olen >= 1 &&
692                                 cand.preference >= 0) {
693                         cand.preference = pref = odata[0];
694                 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
695                         cand.wants_reconfigure = true;
696                 } else if (otype == DHCPV6_OPT_IA_PD && request_prefix) {
697                         struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
698                         uint8_t *oend = odata + olen, *d;
699                         dhcpv6_for_each_option(&h[1], oend, otype, olen, d) {
700                                 if (otype == DHCPV6_OPT_IA_PREFIX && (olen + 4) >=
701                                                 (uint16_t)sizeof(struct dhcpv6_ia_prefix)) {
702                                         struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&d[-4];
703                                         have_pd = p->prefix;
704                                 }
705                         }
706                 } else if (otype == DHCPV6_OPT_IA_NA) {
707                         struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4];
708                         uint8_t *oend = odata + olen, *d;
709                         dhcpv6_for_each_option(&h[1], oend, otype, olen, d)
710                                 if (otype == DHCPV6_OPT_IA_ADDR)
711                                         have_na = true;
712                 }
713         }
714
715         if ((!have_na && na_mode == IA_MODE_FORCE) ||
716                         (!have_pd && pd_mode == IA_MODE_FORCE))
717                 return -1;
718
719         if (na_mode != IA_MODE_NONE && !have_na) {
720                 cand.has_noaddravail = true;
721                 cand.preference -= 1000;
722         }
723
724         if (pd_mode != IA_MODE_NONE) {
725                 if (have_pd)
726                         cand.preference += 2000 + (128 - have_pd);
727                 else
728                         cand.preference -= 2000;
729         }
730
731         if (cand.duid_len > 0) {
732                 cand.ia_na = odhcp6c_move_state(STATE_IA_NA, &cand.ia_na_len);
733                 cand.ia_pd = odhcp6c_move_state(STATE_IA_PD, &cand.ia_pd_len);
734                 odhcp6c_add_state(STATE_SERVER_CAND, &cand, sizeof(cand));
735         }
736
737         return (rc > 1 || (pref == 255 && cand.preference > 0)) ? 1 : -1;
738 }
739
740
741 static int dhcpv6_commit_advert(void)
742 {
743         size_t cand_len;
744         struct dhcpv6_server_cand *c = NULL, *cand =
745                         odhcp6c_get_state(STATE_SERVER_CAND, &cand_len);
746
747         bool retry = false;
748         for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
749                 if (cand[i].has_noaddravail)
750                         retry = true; // We want to try again
751
752                 if (!c || c->preference < cand[i].preference)
753                         c = &cand[i];
754         }
755
756         if (retry && na_mode == IA_MODE_TRY) {
757                 // We give it a second try without the IA_NA
758                 na_mode = IA_MODE_NONE;
759                 return dhcpv6_request(DHCPV6_MSG_SOLICIT);
760         }
761
762         if (c) {
763                 uint16_t hdr[2] = {htons(DHCPV6_OPT_SERVERID),
764                                 htons(c->duid_len)};
765                 odhcp6c_add_state(STATE_SERVER_ID, hdr, sizeof(hdr));
766                 odhcp6c_add_state(STATE_SERVER_ID, c->duid, c->duid_len);
767                 accept_reconfig = c->wants_reconfigure;
768                 if (c->ia_na_len)
769                         odhcp6c_add_state(STATE_IA_NA, c->ia_na, c->ia_na_len);
770                 if (c->ia_pd_len)
771                         odhcp6c_add_state(STATE_IA_PD, c->ia_pd, c->ia_pd_len);
772         }
773
774         for (size_t i = 0; i < cand_len / sizeof(*c); ++i) {
775                 free(cand[i].ia_na);
776                 free(cand[i].ia_pd);
777         }
778         odhcp6c_clear_state(STATE_SERVER_CAND);
779
780         if (!c)
781                 return -1;
782         else if ((request_prefix && c->ia_pd_len) || (na_mode != IA_MODE_NONE && c->ia_na_len))
783                 return DHCPV6_STATEFUL;
784         else
785                 return DHCPV6_STATELESS;
786 }
787
788
789 static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig, const int rc,
790                 const void *opt, const void *end)
791 {
792         dhcpv6_handle_advert(orig, rc, opt, end);
793         if (dhcpv6_commit_advert() < 0)
794                 return -1;
795
796         return dhcpv6_handle_reply(orig, rc, opt, end);
797 }
798
799
800 static int dhcpv6_handle_reply(enum dhcpv6_msg orig, _unused const int rc,
801                 const void *opt, const void *end)
802 {
803         uint8_t *odata;
804         uint16_t otype, olen;
805         uint32_t refresh = UINT32_MAX;
806         int ret = 1;
807         bool handled_status_codes[_DHCPV6_Status_Max] = { false, };
808
809         odhcp6c_expire();
810
811         if (orig == DHCPV6_MSG_UNKNOWN) {
812                 static time_t last_update = 0;
813                 time_t now = odhcp6c_get_milli_time() / 1000;
814
815                 uint32_t elapsed = (last_update > 0) ? now - last_update : 0;
816                 last_update = now;
817
818                 t1 -= elapsed;
819                 t2 -= elapsed;
820                 t3 -= elapsed;
821
822                 if (t1 < 0)
823                         t1 = 0;
824
825                 if (t2 < 0)
826                         t2 = 0;
827
828                 if (t3 < 0)
829                         t3 = 0;
830         }
831
832         if (orig == DHCPV6_MSG_REQUEST && !odhcp6c_is_bound()) {
833                 // Delete NA and PD we have in the state from the Advert
834                 odhcp6c_clear_state(STATE_IA_NA);
835                 odhcp6c_clear_state(STATE_IA_PD);
836         }
837
838         if (opt) {
839                 odhcp6c_clear_state(STATE_DNS);
840                 odhcp6c_clear_state(STATE_SEARCH);
841                 odhcp6c_clear_state(STATE_SNTP_IP);
842                 odhcp6c_clear_state(STATE_SNTP_FQDN);
843                 odhcp6c_clear_state(STATE_SIP_IP);
844                 odhcp6c_clear_state(STATE_SIP_FQDN);
845                 odhcp6c_clear_state(STATE_AFTR_NAME);
846         }
847
848         // Parse and find all matching IAs
849         dhcpv6_for_each_option(opt, end, otype, olen, odata) {
850                 if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)
851                                 && olen > sizeof(struct dhcpv6_ia_hdr)) {
852                         struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]);
853
854                         // Test ID
855                         if (ia_hdr->iaid != 1)
856                                 continue;
857
858                         uint16_t code = DHCPV6_Success;
859                         uint16_t stype, slen;
860                         uint8_t *sdata;
861                         // Get and handle status code
862                         dhcpv6_for_each_option(&ia_hdr[1], odata + olen,
863                                         stype, slen, sdata) {
864                                 if (stype == DHCPV6_OPT_STATUS && slen >= 2) {
865                                         uint8_t *mdata = (slen > 2) ? &sdata[2] : NULL;
866                                         uint16_t mlen = (slen > 2) ? slen - 2 : 0;
867
868                                         code = ((int)sdata[0]) << 8 | ((int)sdata[1]);
869
870                                         if (code == DHCPV6_Success)
871                                                 continue;
872
873                                         dhcpv6_handle_ia_status_code(orig, ia_hdr,
874                                                 code, mdata, mlen, handled_status_codes, &ret);
875
876
877                                         if (ret > 0)
878                                                 return ret;
879                                         break;
880                                 }
881                         }
882
883                         if (code != DHCPV6_Success)
884                                 continue;
885
886                         dhcpv6_parse_ia(ia_hdr, odata + olen + sizeof(*ia_hdr));
887                 } else if (otype == DHCPV6_OPT_STATUS && olen >= 2) {
888                         uint8_t *mdata = (olen > 2) ? &odata[2] : NULL;
889                         uint16_t mlen = (olen > 2) ? olen - 2 : 0;
890                         uint16_t code = ((int)odata[0]) << 8 | ((int)odata[1]);
891
892                         dhcpv6_handle_status_code(orig, code, mdata, mlen, &ret);
893                 }
894                 else if (otype == DHCPV6_OPT_DNS_SERVERS) {
895                         if (olen % 16 == 0)
896                                 odhcp6c_add_state(STATE_DNS, odata, olen);
897                 } else if (otype == DHCPV6_OPT_DNS_DOMAIN) {
898                         odhcp6c_add_state(STATE_SEARCH, odata, olen);
899                 } else if (otype == DHCPV6_OPT_NTP_SERVER) {
900                         uint16_t stype, slen;
901                         uint8_t *sdata;
902                         // Test status and bail if error
903                         dhcpv6_for_each_option(odata, odata + olen,
904                                         stype, slen, sdata) {
905                                 if (slen == 16 && (stype == NTP_MC_ADDR ||
906                                                 stype == NTP_SRV_ADDR))
907                                         odhcp6c_add_state(STATE_SNTP_IP,
908                                                         sdata, slen);
909                                 else if (slen > 0 && stype == NTP_SRV_FQDN)
910                                         odhcp6c_add_state(STATE_SNTP_FQDN,
911                                                         sdata, slen);
912                         }
913                 } else if (otype == DHCPV6_OPT_SIP_SERVER_A) {
914                         if (olen == 16)
915                                 odhcp6c_add_state(STATE_SIP_IP, odata, olen);
916                 } else if (otype == DHCPV6_OPT_SIP_SERVER_D) {
917                         odhcp6c_add_state(STATE_SIP_FQDN, odata, olen);
918                 } else if (otype == DHCPV6_OPT_INFO_REFRESH && olen >= 4) {
919                         refresh = ntohl(*((uint32_t*)odata));
920                 } else if (otype == DHCPV6_OPT_AUTH && olen == -4 +
921                                 sizeof(struct dhcpv6_auth_reconfigure)) {
922                         struct dhcpv6_auth_reconfigure *r = (void*)&odata[-4];
923                         if (r->protocol == 3 && r->algorithm == 1 &&
924                                         r->reconf_type == 1)
925                                 memcpy(reconf_key, r->key, sizeof(r->key));
926                 } else if (otype == DHCPV6_OPT_AFTR_NAME && olen > 3) {
927                         size_t cur_len;
928                         odhcp6c_get_state(STATE_AFTR_NAME, &cur_len);
929                         if (cur_len == 0)
930                                 odhcp6c_add_state(STATE_AFTR_NAME, odata, olen);
931                 } else if (otype != DHCPV6_OPT_CLIENTID &&
932                                 otype != DHCPV6_OPT_SERVERID) {
933                         odhcp6c_add_state(STATE_CUSTOM_OPTS,
934                                         &odata[-4], olen + 4);
935                 }
936         }
937
938         if (orig != DHCPV6_MSG_INFO_REQ) {
939                 // Update refresh timers if no fatal status code was received
940                 if ((ret > 0) && dhcpv6_calc_refresh_timers()) {
941                         switch (orig) {
942                         case DHCPV6_MSG_RENEW:
943                                 // Send further renews if T1 is not set
944                                 if (!t1)
945                                         ret = -1;
946                                 break;
947                         case DHCPV6_MSG_REBIND:
948                                 // Send further rebinds if T1 and T2 is not set
949                                 if (!t1 && !t2)
950                                         ret = -1;
951                                 break;
952
953                         default :
954                                 break;
955                         }
956                 }
957         }
958         else if (ret > 0)
959                 t1 = refresh;
960
961         return ret;
962 }
963
964
965 static int dhcpv6_parse_ia(void *opt, void *end)
966 {
967         struct dhcpv6_ia_hdr *ia_hdr = (struct dhcpv6_ia_hdr *)opt;
968         int parsed_ia = 0;
969         uint32_t t1, t2;
970         uint16_t otype, olen;
971         uint8_t *odata;
972
973         t1 = ntohl(ia_hdr->t1);
974         t2 = ntohl(ia_hdr->t2);
975
976         if (t1 > t2)
977                 return 0;
978
979         // Update address IA
980         dhcpv6_for_each_option(&ia_hdr[1], end, otype, olen, odata) {
981                 struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0,
982                                 IN6ADDR_ANY_INIT, 0, 0, 0, 0, 0};
983
984                 if (otype == DHCPV6_OPT_IA_PREFIX) {
985                         struct dhcpv6_ia_prefix *prefix = (void*)&odata[-4];
986                         if (olen + 4U < sizeof(*prefix))
987                                 continue;
988
989                         entry.valid = ntohl(prefix->valid);
990                         entry.preferred = ntohl(prefix->preferred);
991
992                         if (entry.preferred > entry.valid)
993                                 continue;
994
995                         entry.t1 = (t1 ? t1 : (entry.preferred != UINT32_MAX ? 0.5 * entry.preferred : UINT32_MAX));
996                         entry.t2 = (t2 ? t2 : (entry.preferred != UINT32_MAX ? 0.8 * entry.preferred : UINT32_MAX));
997                         if (entry.t1 > entry.t2)
998                                 entry.t1 = entry.t2;
999
1000                         entry.length = prefix->prefix;
1001                         entry.target = prefix->addr;
1002                         uint16_t stype, slen;
1003                         uint8_t *sdata;
1004
1005 #ifdef EXT_PREFIX_CLASS
1006                         // Find prefix class, if any
1007                         dhcpv6_for_each_option(&prefix[1], odata + olen,
1008                                         stype, slen, sdata)
1009                                 if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
1010                                         entry.class = sdata[0] << 8 | sdata[1];
1011 #endif
1012
1013                         // Parse PD-exclude
1014                         bool ok = true;
1015                         dhcpv6_for_each_option(odata + sizeof(*prefix) - 4U,
1016                                         odata + olen, stype, slen, sdata) {
1017                                 if (stype != DHCPV6_OPT_PD_EXCLUDE || slen < 2)
1018                                         continue;
1019
1020                                 uint8_t elen = sdata[0];
1021                                 if (elen > 64)
1022                                         elen = 64;
1023
1024                                 if (elen <= 32 || elen <= entry.length) {
1025                                         ok = false;
1026                                         continue;
1027                                 }
1028
1029
1030                                 uint8_t bytes = ((elen - entry.length - 1) / 8) + 1;
1031                                 if (slen <= bytes) {
1032                                         ok = false;
1033                                         continue;
1034                                 }
1035
1036                                 uint32_t exclude = 0;
1037                                 do {
1038                                         exclude = exclude << 8 | sdata[bytes];
1039                                 } while (--bytes);
1040
1041                                 exclude >>= 8 - ((elen - entry.length) % 8);
1042                                 exclude <<= 64 - elen;
1043
1044                                 // Abusing router & priority fields for exclusion
1045                                 entry.router = entry.target;
1046                                 entry.router.s6_addr32[1] |= htonl(exclude);
1047                                 entry.priority = elen;
1048                         }
1049
1050                         if (ok) {
1051                                 odhcp6c_update_entry(STATE_IA_PD, &entry);
1052                                 parsed_ia++;
1053                         }
1054
1055                         entry.priority = 0;
1056                         memset(&entry.router, 0, sizeof(entry.router));
1057                 } else if (otype == DHCPV6_OPT_IA_ADDR) {
1058                         struct dhcpv6_ia_addr *addr = (void*)&odata[-4];
1059                         if (olen + 4U < sizeof(*addr))
1060                                 continue;
1061
1062                         entry.preferred = ntohl(addr->preferred);
1063                         entry.valid = ntohl(addr->valid);
1064
1065                         if (entry.preferred > entry.valid)
1066                                 continue;
1067
1068                         entry.t1 = (t1 ? t1 : (entry.preferred != UINT32_MAX ? 0.5 * entry.preferred : UINT32_MAX));
1069                         entry.t2 = (t2 ? t2 : (entry.preferred != UINT32_MAX ? 0.8 * entry.preferred : UINT32_MAX));
1070                         if (entry.t1 > entry.t2)
1071                                 entry.t1 = entry.t2;
1072
1073                         entry.length = 128;
1074                         entry.target = addr->addr;
1075
1076 #ifdef EXT_PREFIX_CLASS
1077                         uint16_t stype, slen;
1078                         uint8_t *sdata;
1079                         // Find prefix class, if any
1080                         dhcpv6_for_each_option(&addr[1], odata + olen,
1081                                         stype, slen, sdata)
1082                                 if (stype == DHCPV6_OPT_PREFIX_CLASS && slen == 2)
1083                                         entry.class = sdata[0] << 8 | sdata[1];
1084 #endif
1085
1086                         odhcp6c_update_entry(STATE_IA_NA, &entry);
1087                         parsed_ia++;
1088                 }
1089         }
1090         return parsed_ia;
1091 }
1092
1093
1094 static int dhcpv6_calc_refresh_timers(void)
1095 {
1096         struct odhcp6c_entry *e;
1097         size_t ia_na_entries, ia_pd_entries, i;
1098         int64_t l_t1 = UINT32_MAX, l_t2 = UINT32_MAX, l_t3 = 0;
1099
1100         e = odhcp6c_get_state(STATE_IA_NA, &ia_na_entries);
1101         ia_na_entries /= sizeof(*e);
1102         for (i = 0; i < ia_na_entries; i++) {
1103                 if (e[i].t1 < l_t1)
1104                         l_t1 = e[i].t1;
1105
1106                 if (e[i].t2 < l_t2)
1107                         l_t2 = e[i].t2;
1108
1109                 if (e[i].valid > l_t3)
1110                         l_t3 = e[i].valid;
1111         }
1112
1113         e = odhcp6c_get_state(STATE_IA_PD, &ia_pd_entries);
1114         ia_pd_entries /= sizeof(*e);
1115         for (i = 0; i < ia_pd_entries; i++) {
1116                 if (e[i].t1 < l_t1)
1117                         l_t1 = e[i].t1;
1118
1119                 if (e[i].t2 < l_t2)
1120                         l_t2 = e[i].t2;
1121
1122                 if (e[i].valid > l_t3)
1123                         l_t3 = e[i].valid;
1124         }
1125
1126         if (ia_pd_entries || ia_na_entries) {
1127                 t1 = l_t1;
1128                 t2 = l_t2;
1129                 t3 = l_t3;
1130         }
1131
1132         return (int)(ia_pd_entries + ia_na_entries);
1133 }
1134
1135
1136 static void dhcpv6_log_status_code(const uint16_t code, const char *scope,
1137                 const void *status_msg, const int len)
1138 {
1139         uint8_t buf[len + 3];
1140
1141         memset(buf, 0, sizeof(buf));
1142         if (len) {
1143                 buf[0] = '(';
1144                 memcpy(&buf[1], status_msg, len);
1145                 buf[len + 1] = ')';
1146         }
1147
1148         syslog(LOG_WARNING, "Server returned %s status %i %s",
1149                 scope, code, buf);
1150 }
1151
1152
1153 static void dhcpv6_handle_status_code(const enum dhcpv6_msg orig,
1154                 const uint16_t code, const void *status_msg, const int len,
1155                 int *ret)
1156 {
1157         dhcpv6_log_status_code(code, "message", status_msg, len);
1158
1159         switch (code) {
1160         case DHCPV6_UnspecFail:
1161                 // Generic failure
1162                 *ret = 0;
1163                 break;
1164
1165         case DHCPV6_UseMulticast:
1166                 // TODO handle multicast status code
1167                 break;
1168
1169         case DHCPV6_NoAddrsAvail:
1170         case DHCPV6_NoPrefixAvail:
1171                 if (orig == DHCPV6_MSG_REQUEST)
1172                         *ret = 0; // Failure
1173                 break;
1174
1175         default:
1176                 break;
1177         }
1178 }
1179
1180
1181 static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig,
1182                 const struct dhcpv6_ia_hdr *ia_hdr, const uint16_t code,
1183                 const void *status_msg, const int len,
1184                 bool handled_status_codes[_DHCPV6_Status_Max], int *ret)
1185 {
1186         dhcpv6_log_status_code(code, ia_hdr->type == DHCPV6_OPT_IA_NA ?
1187                 "IA_NA" : "IA_PD", status_msg, len);
1188
1189         switch (code) {
1190         case DHCPV6_NoBinding:
1191                 switch (orig) {
1192                 case DHCPV6_MSG_RENEW:
1193                 case DHCPV6_MSG_REBIND:
1194                         if ((*ret > 0) && !handled_status_codes[code])
1195                                 *ret = dhcpv6_request(DHCPV6_MSG_REQUEST);
1196                         break;
1197
1198                 default:
1199                         break;
1200                 }
1201                 break;
1202
1203         case DHCPV6_NoAddrsAvail:
1204         case DHCPV6_NoPrefixAvail:
1205                 switch (orig) {
1206                 case DHCPV6_MSG_REQUEST:
1207                         if (*ret != 0)
1208                                 *ret = 0;
1209                         break;
1210                 default:
1211                         break;
1212                 }
1213                 break;
1214
1215         case DHCPV6_NotOnLink:
1216                 // TODO handle not onlink in case of confirm
1217                 break;
1218
1219         default:
1220                 break;
1221         }
1222 }