src/dhcpv6-ia.c

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