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