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                         dhcpv6_ia_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 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->head.next)
 212                 list_del(&a->head);
 213
 214         if (a->lease_list.next)
 215                 list_del(&a->lease_list);
 216
 217         if (a->reconf_cnt)
 218                 stop_reconf(a);
 219
 220         free(a->managed);
 221         free(a->hostname);
 222         free(a);
 223 }
 224
 225 void dhcpv6_ia_enum_addrs(struct interface *iface, struct dhcp_assignment *c,
 226                           time_t now, dhcpv6_binding_cb_handler_t func, void *arg)
 227 {
 228         struct odhcpd_ipaddr *addrs = (c->managed) ? c->managed : iface->addr6;
 229         size_t addrlen = (c->managed) ? (size_t)c->managed_size : iface->addr6_len;
 230         size_t m = get_preferred_addr(addrs, addrlen);
 231
 232         for (size_t i = 0; i < addrlen; ++i) {
 233                 struct in6_addr addr;
 234                 uint32_t pref, valid;
 235                 int prefix = c->managed ? addrs[i].prefix : c->length;
 236
 237                 if (!valid_addr(&addrs[i], now))
 238                         continue;
 239
 240                 addr = addrs[i].addr.in6;
 241                 pref = addrs[i].preferred;
 242                 valid = addrs[i].valid;
 243                 if (prefix == 128) {
 244                         if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs))
 245                                 continue;
 246
 247                         addr.s6_addr32[3] = htonl(c->assigned);
 248                 } else {
 249                         if (!valid_prefix_length(c, addrs[i].prefix))
 250                                 continue;
 251
 252                         addr.s6_addr32[1] |= htonl(c->assigned);
 253                         addr.s6_addr32[2] = addr.s6_addr32[3] = 0;
 254                 }
 255
 256                 if (pref != UINT32_MAX)
 257                         pref -= now;
 258
 259                 if (valid != UINT32_MAX)
 260                         valid -= now;
 261
 262                 func(&addr, prefix, pref, valid, arg);
 263         }
 264 }
 265
 266 struct write_ctxt {
 267         FILE *fp;
 268         md5_ctx_t md5;
 269         struct dhcp_assignment *c;
 270         struct interface *iface;
 271         char *buf;
 272         int buf_len;
 273         int buf_idx;
 274 };
 275
 276 void dhcpv6_write_ia_addr(struct in6_addr *addr, int prefix, _unused uint32_t pref,
 277                                 _unused uint32_t valid, void *arg)
 278 {
 279         struct write_ctxt *ctxt = (struct write_ctxt *)arg;
 280         char ipbuf[INET6_ADDRSTRLEN];
 281
 282         inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf) - 1);
 283
 284         if (ctxt->c->length == 128 && ctxt->c->hostname &&
 285             !(ctxt->c->flags & OAF_BROKEN_HOSTNAME)) {
 286                 fputs(ipbuf, ctxt->fp);
 287
 288                 char b[256];
 289                 if (dn_expand(ctxt->iface->search, ctxt->iface->search + ctxt->iface->search_len,
 290                                 ctxt->iface->search, b, sizeof(b)) > 0)
 291                         fprintf(ctxt->fp, "\t%s.%s", ctxt->c->hostname, b);
 292
 293                 fprintf(ctxt->fp, "\t%s\n", ctxt->c->hostname);
 294                 md5_hash(ipbuf, strlen(ipbuf), &ctxt->md5);
 295                 md5_hash(ctxt->c->hostname, strlen(ctxt->c->hostname), &ctxt->md5);
 296         }
 297
 298         ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx,ctxt->buf_len - ctxt->buf_idx,
 299                                         "%s/%d ", ipbuf, prefix);
 300 }
 301
 302 void dhcpv6_ia_write_statefile(void)
 303 {
 304         struct write_ctxt ctxt;
 305
 306         md5_begin(&ctxt.md5);
 307
 308         if (config.dhcp_statefile) {
 309                 time_t now = odhcpd_time(), wall_time = time(NULL);
 310                 int fd = open(config.dhcp_statefile, O_CREAT | O_WRONLY | O_CLOEXEC, 0644);
 311                 char leasebuf[512];
 312
 313                 if (fd < 0)
 314                         return;
 315                 int ret;
 316                 ret = lockf(fd, F_LOCK, 0);
 317                 if (ret < 0) {
 318                         close(fd);
 319                         return;
 320                 }
 321                 if (ftruncate(fd, 0) < 0) {}
 322
 323                 ctxt.fp = fdopen(fd, "w");
 324                 if (!ctxt.fp) {
 325                         close(fd);
 326                         return;
 327                 }
 328
 329                 ctxt.buf = leasebuf;
 330                 ctxt.buf_len = sizeof(leasebuf);
 331
 332                 avl_for_each_element(&interfaces, ctxt.iface, avl) {
 333                         if (ctxt.iface->dhcpv6 != MODE_SERVER &&
 334                                         ctxt.iface->dhcpv4 != MODE_SERVER)
 335                                 continue;
 336
 337                         if (ctxt.iface->dhcpv6 == MODE_SERVER &&
 338                                         ctxt.iface->ia_assignments.next) {
 339                                 list_for_each_entry(ctxt.c, &ctxt.iface->ia_assignments, head) {
 340                                         if (!(ctxt.c->flags & OAF_BOUND) || ctxt.c->managed_size < 0)
 341                                                 continue;
 342
 343                                         char duidbuf[264];
 344
 345                                         odhcpd_hexlify(duidbuf, ctxt.c->clid_data, ctxt.c->clid_len);
 346
 347                                         /* iface DUID iaid hostname lifetime assigned length [addrs...] */
 348                                         ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s %x %s%s %ld %x %u ",
 349                                                                 ctxt.iface->ifname, duidbuf, ntohl(ctxt.c->iaid),
 350                                                                 (ctxt.c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
 351                                                                 (ctxt.c->hostname ? ctxt.c->hostname : "-"),
 352                                                                 (ctxt.c->valid_until > now ?
 353                                                                         (ctxt.c->valid_until - now + wall_time) :
 354                                                                         (INFINITE_VALID(ctxt.c->valid_until) ? -1 : 0)),
 355                                                                 ctxt.c->assigned, (unsigned)ctxt.c->length);
 356
 357                                         if (INFINITE_VALID(ctxt.c->valid_until) || ctxt.c->valid_until > now)
 358                                                 dhcpv6_ia_enum_addrs(ctxt.iface, ctxt.c, now,
 359                                                                         dhcpv6_write_ia_addr, &ctxt);
 360
 361                                         ctxt.buf[ctxt.buf_idx - 1] = '\n';
 362                                         fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
 363                                 }
 364                         }
 365
 366                         if (ctxt.iface->dhcpv4 == MODE_SERVER &&
 367                                         ctxt.iface->dhcpv4_assignments.next) {
 368                                 struct dhcp_assignment *c;
 369                                 list_for_each_entry(c, &ctxt.iface->dhcpv4_assignments, head) {
 370                                         if (!(c->flags & OAF_BOUND))
 371                                                 continue;
 372
 373                                         char ipbuf[INET6_ADDRSTRLEN];
 374                                         char duidbuf[16];
 375                                         odhcpd_hexlify(duidbuf, c->hwaddr, sizeof(c->hwaddr));
 376
 377                                         /* iface DUID iaid hostname lifetime assigned length [addrs...] */
 378                                         ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s ipv4 %s%s %ld %x 32 ",
 379                                                                 ctxt.iface->ifname, duidbuf,
 380                                                                 (c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
 381                                                                 (c->hostname ? c->hostname : "-"),
 382                                                                 (c->valid_until > now ?
 383                                                                         (c->valid_until - now + wall_time) :
 384                                                                         (INFINITE_VALID(c->valid_until) ? -1 : 0)),
 385                                                                 ntohl(c->addr));
 386
 387                                         struct in_addr addr = {.s_addr = c->addr};
 388                                         inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf) - 1);
 389
 390                                         if (c->hostname && !(c->flags & OAF_BROKEN_HOSTNAME)) {
 391                                                 fputs(ipbuf, ctxt.fp);
 392
 393                                                 char b[256];
 394                                                 if (dn_expand(ctxt.iface->search,
 395                                                                 ctxt.iface->search + ctxt.iface->search_len,
 396                                                                 ctxt.iface->search, b, sizeof(b)) > 0)
 397                                                         fprintf(ctxt.fp, "\t%s.%s", c->hostname, b);
 398
 399                                                 fprintf(ctxt.fp, "\t%s\n", c->hostname);
 400                                                 md5_hash(ipbuf, strlen(ipbuf), &ctxt.md5);
 401                                                 md5_hash(c->hostname, strlen(c->hostname), &ctxt.md5);
 402                                         }
 403
 404                                         ctxt.buf_idx += snprintf(ctxt.buf + ctxt.buf_idx,
 405                                                                         ctxt.buf_len - ctxt.buf_idx,
 406                                                                         "%s/32 ", ipbuf);
 407                                         ctxt.buf[ctxt.buf_idx - 1] = '\n';
 408                                         fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
 409                                 }
 410                         }
 411                 }
 412
 413                 fclose(ctxt.fp);
 414         }
 415
 416         uint8_t newmd5[16];
 417         md5_end(newmd5, &ctxt.md5);
 418
 419         if (config.dhcp_cb && memcmp(newmd5, statemd5, sizeof(newmd5))) {
 420                 memcpy(statemd5, newmd5, sizeof(statemd5));
 421                 char *argv[2] = {config.dhcp_cb, NULL};
 422                 if (!vfork()) {
 423                         execv(argv[0], argv);
 424                         _exit(128);
 425                 }
 426         }
 427 }
 428
 429 static void __apply_lease(struct interface *iface, struct dhcp_assignment *a,
 430                 struct odhcpd_ipaddr *addrs, ssize_t addr_len, bool add)
 431 {
 432         if (a->length > 64)
 433                 return;
 434
 435         for (ssize_t i = 0; i < addr_len; ++i) {
 436                 struct in6_addr prefix = addrs[i].addr.in6;
 437                 prefix.s6_addr32[1] |= htonl(a->assigned);
 438                 prefix.s6_addr32[2] = prefix.s6_addr32[3] = 0;
 439                 netlink_setup_route(&prefix, (a->managed_size) ? addrs[i].prefix : a->length,
 440                                 iface->ifindex, &a->peer.sin6_addr, 1024, add);
 441         }
 442 }
 443
 444 static void apply_lease(struct interface *iface, struct dhcp_assignment *a, bool add)
 445 {
 446         struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
 447         ssize_t addrlen = (a->managed) ? a->managed_size : (ssize_t)iface->addr6_len;
 448
 449         __apply_lease(iface, a, addrs, addrlen, add);
 450 }
 451
 452 /* Set border assignment size based on the IPv6 address prefixes */
 453 static void set_border_assignment_size(struct interface *iface, struct dhcp_assignment *b)
 454 {
 455         time_t now = odhcpd_time();
 456         int minprefix = -1;
 457
 458         for (size_t i = 0; i < iface->addr6_len; ++i) {
 459                 if (iface->addr6[i].preferred > (uint32_t)now &&
 460                                 iface->addr6[i].prefix < 64 &&
 461                                 iface->addr6[i].prefix > minprefix)
 462                         minprefix = iface->addr6[i].prefix;
 463         }
 464
 465         if (minprefix > 32 && minprefix <= 64)
 466                 b->assigned = 1U << (64 - minprefix);
 467         else
 468                 b->assigned = 0;
 469 }
 470
 471 /* More data was received from TCP connection */
 472 static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
 473 {
 474         struct ustream_fd *fd = container_of(s, struct ustream_fd, stream);
 475         struct dhcp_assignment *c = container_of(fd, struct dhcp_assignment, managed_sock);
 476         time_t now = odhcpd_time();
 477         bool first = c->managed_size < 0;
 478
 479         for (;;) {
 480                 int pending;
 481                 char *data = ustream_get_read_buf(s, &pending);
 482                 char *end = memmem(data, pending, "\n\n", 2);
 483
 484                 if (!end)
 485                         break;
 486
 487                 end += 2;
 488                 end[-1] = 0;
 489
 490                 c->managed_size = 0;
 491                 if (c->accept_reconf)
 492                         c->reconf_cnt = 1;
 493
 494                 char *saveptr;
 495                 for (char *line = strtok_r(data, "\n", &saveptr); line; line = strtok_r(NULL, "\n", &saveptr)) {
 496                         c->managed = realloc(c->managed, (c->managed_size + 1) * sizeof(*c->managed));
 497                         struct odhcpd_ipaddr *n = &c->managed[c->managed_size];
 498
 499                         char *saveptr2, *x = strtok_r(line, "/", &saveptr2);
 500                         if (!x || inet_pton(AF_INET6, x, &n->addr) < 1)
 501                                 continue;
 502
 503                         x = strtok_r(NULL, ",", &saveptr2);
 504                         if (sscanf(x, "%hhu", &n->prefix) < 1)
 505                                 continue;
 506
 507                         x = strtok_r(NULL, ",", &saveptr2);
 508                         if (sscanf(x, "%u", &n->preferred) < 1)
 509                                 continue;
 510
 511                         x = strtok_r(NULL, ",", &saveptr2);
 512                         if (sscanf(x, "%u", &n->valid) < 1)
 513                                 continue;
 514
 515                         if (n->preferred > n->valid)
 516                                 continue;
 517
 518                         if (UINT32_MAX - now < n->preferred)
 519                                 n->preferred = UINT32_MAX;
 520                         else
 521                                 n->preferred += now;
 522
 523                         if (UINT32_MAX - now < n->valid)
 524                                 n->valid = UINT32_MAX;
 525                         else
 526                                 n->valid += now;
 527
 528                         n->dprefix = 0;
 529
 530                         ++c->managed_size;
 531                 }
 532
 533                 ustream_consume(s, end - data);
 534         }
 535
 536         if (first && c->managed_size == 0)
 537                 dhcpv6_ia_free_assignment(c);
 538         else if (first && !(c->flags & OAF_STATIC))
 539                 c->valid_until = now + 150;
 540 }
 541
 542
 543 /* TCP transmission has ended, either because of success or timeout or other error */
 544 static void managed_handle_pd_done(struct ustream *s)
 545 {
 546         struct ustream_fd *fd = container_of(s, struct ustream_fd, stream);
 547         struct dhcp_assignment *c = container_of(fd, struct dhcp_assignment, managed_sock);
 548
 549         if (!(c->flags & OAF_STATIC))
 550                 c->valid_until = odhcpd_time() + 15;
 551
 552         c->managed_size = 0;
 553
 554         if (c->accept_reconf)
 555                 c->reconf_cnt = 1;
 556 }
 557
 558 static bool assign_pd(struct interface *iface, struct dhcp_assignment *assign)
 559 {
 560         struct dhcp_assignment *c;
 561
 562         if (iface->dhcpv6_pd_manager[0]) {
 563                 int fd = usock(USOCK_UNIX | USOCK_TCP, iface->dhcpv6_pd_manager, NULL);
 564                 if (fd >= 0) {
 565                         struct pollfd pfd = { .fd = fd, .events = POLLIN };
 566                         char iaidbuf[298];
 567
 568                         odhcpd_hexlify(iaidbuf, assign->clid_data, assign->clid_len);
 569
 570                         assign->managed_sock.stream.notify_read = managed_handle_pd_data;
 571                         assign->managed_sock.stream.notify_state = managed_handle_pd_done;
 572                         ustream_fd_init(&assign->managed_sock, fd);
 573                         ustream_printf(&assign->managed_sock.stream, "%s,%x\n::/%d,0,0\n\n",
 574                                         iaidbuf, assign->iaid, assign->length);
 575                         ustream_write_pending(&assign->managed_sock.stream);
 576                         assign->managed_size = -1;
 577
 578                         if (!(assign->flags & OAF_STATIC))
 579                                 assign->valid_until = odhcpd_time() + 15;
 580
 581                         list_add(&assign->head, &iface->ia_assignments);
 582
 583                         /* Wait initial period of up to 250ms for immediate assignment */
 584                         if (poll(&pfd, 1, 250) < 0) {
 585                                 syslog(LOG_ERR, "poll(): %m");
 586                                 return false;
 587                         }
 588
 589                         managed_handle_pd_data(&assign->managed_sock.stream, 0);
 590
 591                         if (fcntl(fd, F_GETFL) >= 0 && assign->managed_size > 0)
 592                                 return true;
 593                 }
 594
 595                 return false;
 596         } else if (iface->addr6_len < 1)
 597                 return false;
 598
 599         /* Try honoring the hint first */
 600         uint32_t current = 1, asize = (1 << (64 - assign->length)) - 1;
 601         if (assign->assigned) {
 602                 list_for_each_entry(c, &iface->ia_assignments, head) {
 603                         if (c->length == 128 || c->length == 0)
 604                                 continue;
 605
 606                         if (assign->assigned >= current && assign->assigned + asize < c->assigned) {
 607                                 list_add_tail(&assign->head, &c->head);
 608
 609                                 if (assign->flags & OAF_BOUND)
 610                                         apply_lease(iface, assign, true);
 611
 612                                 return true;
 613                         }
 614
 615                         if (c->assigned != 0)
 616                                 current = (c->assigned + (1 << (64 - c->length)));
 617                 }
 618         }
 619
 620         /* Fallback to a variable assignment */
 621         current = 1;
 622         list_for_each_entry(c, &iface->ia_assignments, head) {
 623                 if (c->length == 128 || c->length == 0)
 624                         continue;
 625
 626                 current = (current + asize) & (~asize);
 627                 if (current + asize < c->assigned) {
 628                         assign->assigned = current;
 629                         list_add_tail(&assign->head, &c->head);
 630
 631                         if (assign->flags & OAF_BOUND)
 632                                 apply_lease(iface, assign, true);
 633
 634                         return true;
 635                 }
 636
 637                 if (c->assigned != 0)
 638                         current = (c->assigned + (1 << (64 - c->length)));
 639         }
 640
 641         return false;
 642 }
 643
 644 static bool assign_na(struct interface *iface, struct dhcp_assignment *a)
 645 {
 646         struct dhcp_assignment *c;
 647         uint32_t seed = 0;
 648
 649         /* Preconfigured assignment by static lease */
 650         if (a->assigned) {
 651                 list_for_each_entry(c, &iface->ia_assignments, head) {
 652                         if (c->length == 0)
 653                                 continue;
 654
 655                         if (c->assigned > a->assigned || c->length != 128) {
 656                                 list_add_tail(&a->head, &c->head);
 657                                 return true;
 658                         } else if (c->assigned == a->assigned)
 659                                 return false;
 660                 }
 661         }
 662
 663         /* Seed RNG with checksum of DUID */
 664         for (size_t i = 0; i < a->clid_len; ++i)
 665                 seed += a->clid_data[i];
 666         srand(seed);
 667
 668         /* Try to assign up to 100x */
 669         for (size_t i = 0; i < 100; ++i) {
 670                 uint32_t try;
 671                 do try = ((uint32_t)rand()) % 0x0fff; while (try < 0x100);
 672
 673                 if (config_find_lease_by_hostid(try))
 674                         continue;
 675
 676                 list_for_each_entry(c, &iface->ia_assignments, head) {
 677                         if (c->length == 0)
 678                                 continue;
 679
 680                         if (c->assigned > try || c->length != 128) {
 681                                 a->assigned = try;
 682                                 list_add_tail(&a->head, &c->head);
 683                                 return true;
 684                         } else if (c->assigned == try)
 685                                 break;
 686                 }
 687         }
 688
 689         return false;
 690 }
 691
 692 static void handle_addrlist_change(struct netevent_handler_info *info)
 693 {
 694         struct interface *iface = info->iface;
 695         struct dhcp_assignment *c, *d, *border = list_last_entry(
 696                         &iface->ia_assignments, struct dhcp_assignment, head);
 697         struct list_head reassign = LIST_HEAD_INIT(reassign);
 698         time_t now = odhcpd_time();
 699
 700         list_for_each_entry(c, &iface->ia_assignments, head) {
 701                 if (c != border && iface->ra_managed == RA_MANAGED_NO_MFLAG
 702                                 && (c->flags & OAF_BOUND))
 703                         __apply_lease(iface, c, info->addrs_old.addrs,
 704                                         info->addrs_old.len, false);
 705         }
 706
 707         set_border_assignment_size(iface, border);
 708
 709         list_for_each_entry_safe(c, d, &iface->ia_assignments, head) {
 710                 if (c->clid_len == 0 || (!INFINITE_VALID(c->valid_until) && c->valid_until < now) ||
 711                                 c->managed_size)
 712                         continue;
 713
 714                 if (c->length < 128 && c->assigned >= border->assigned && c != border)
 715                         list_move(&c->head, &reassign);
 716                 else if (c != border && (c->flags & OAF_BOUND))
 717                         apply_lease(iface, c, true);
 718
 719                 if (c->accept_reconf && c->reconf_cnt == 0) {
 720                         struct dhcp_assignment *a;
 721
 722                         start_reconf(c);
 723
 724                         /* Leave all other assignments of that client alone */
 725                         list_for_each_entry(a, &iface->ia_assignments, head)
 726                                 if (a != c && a->clid_len == c->clid_len &&
 727                                                 !memcmp(a->clid_data, c->clid_data, a->clid_len))
 728                                         a->reconf_cnt = INT_MAX;
 729                 }
 730         }
 731
 732         while (!list_empty(&reassign)) {
 733                 c = list_first_entry(&reassign, struct dhcp_assignment, head);
 734                 list_del(&c->head);
 735                 if (!assign_pd(iface, c)) {
 736                         c->assigned = 0;
 737                         list_add(&c->head, &iface->ia_assignments);
 738                 }
 739         }
 740
 741         dhcpv6_ia_write_statefile();
 742 }
 743
 744 static void reconf_timeout_cb(struct uloop_timeout *event)
 745 {
 746         struct dhcp_assignment *a = container_of(event, struct dhcp_assignment, reconf_timer);
 747
 748         if (a->reconf_cnt > 0 && a->reconf_cnt < DHCPV6_REC_MAX_RC) {
 749                 send_reconf(a);
 750                 uloop_timeout_set(&a->reconf_timer,
 751                                         DHCPV6_REC_TIMEOUT << a->reconf_cnt);
 752                 a->reconf_cnt++;
 753         } else
 754                 stop_reconf(a);
 755 }
 756
 757 static void start_reconf(struct dhcp_assignment *a)
 758 {
 759         uloop_timeout_set(&a->reconf_timer,
 760                                 DHCPV6_REC_TIMEOUT << a->reconf_cnt);
 761         a->reconf_timer.cb = reconf_timeout_cb;
 762         a->reconf_cnt++;
 763
 764         send_reconf(a);
 765 }
 766
 767 static void stop_reconf(struct dhcp_assignment *a)
 768 {
 769         uloop_timeout_cancel(&a->reconf_timer);
 770         a->reconf_cnt = 0;
 771         a->reconf_timer.cb = NULL;
 772 }
 773
 774 static void valid_until_cb(struct uloop_timeout *event)
 775 {
 776         struct interface *iface;
 777         time_t now = odhcpd_time();
 778
 779         avl_for_each_element(&interfaces, iface, avl) {
 780                 struct dhcp_assignment *a, *n;
 781
 782                 if (iface->dhcpv6 != MODE_SERVER || iface->ia_assignments.next == NULL)
 783                         continue;
 784
 785                 list_for_each_entry_safe(a, n, &iface->ia_assignments, head) {
 786                         if (!INFINITE_VALID(a->valid_until) && a->valid_until < now) {
 787                                 if ((a->length < 128 && a->clid_len > 0) ||
 788                                                 (a->length == 128 && a->clid_len == 0))
 789                                         dhcpv6_ia_free_assignment(a);
 790
 791                         }
 792                 }
 793         }
 794         uloop_timeout_set(event, 1000);
 795 }
 796
 797 static size_t build_ia(uint8_t *buf, size_t buflen, uint16_t status,
 798                 const struct dhcpv6_ia_hdr *ia, struct dhcp_assignment *a,
 799                 struct interface *iface, bool request)
 800 {
 801         struct dhcpv6_ia_hdr o_ia = {
 802                 .type = ia->type,
 803                 .len = 0,
 804                 .iaid = ia->iaid,
 805                 .t1 = 0,
 806                 .t2 = 0,
 807         };
 808         size_t ia_len = sizeof(o_ia);
 809         time_t now = odhcpd_time();
 810
 811         if (buflen < ia_len)
 812                 return 0;
 813
 814         if (status) {
 815                 struct __attribute__((packed)) {
 816                         uint16_t type;
 817                         uint16_t len;
 818                         uint16_t val;
 819                 } o_status = {
 820                         .type = htons(DHCPV6_OPT_STATUS),
 821                         .len = htons(sizeof(o_status) - 4),
 822                         .val = htons(status),
 823                 };
 824
 825                 memcpy(buf + ia_len, &o_status, sizeof(o_status));
 826                 ia_len += sizeof(o_status);
 827
 828                 o_ia.len = htons(ia_len - 4);
 829                 memcpy(buf, &o_ia, sizeof(o_ia));
 830
 831                 return ia_len;
 832         }
 833
 834         if (a) {
 835                 uint32_t leasetime;
 836
 837                 if (a->leasetime)
 838                         leasetime = a->leasetime;
 839                 else
 840                         leasetime = iface->dhcpv4_leasetime;
 841
 842                 uint32_t pref = leasetime;
 843                 uint32_t valid = leasetime;
 844
 845                 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
 846                 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->addr6_len;
 847                 size_t m = get_preferred_addr(addrs, addrlen);
 848
 849                 for (size_t i = 0; i < addrlen; ++i) {
 850                         uint32_t prefix_pref = addrs[i].preferred;
 851                         uint32_t prefix_valid = addrs[i].valid;
 852
 853                         if (!valid_addr(&addrs[i], now))
 854                                 continue;
 855
 856                         if (prefix_pref != UINT32_MAX)
 857                                 prefix_pref -= now;
 858
 859                         if (prefix_valid != UINT32_MAX)
 860                                 prefix_valid -= now;
 861
 862                         if (a->length < 128) {
 863                                 struct dhcpv6_ia_prefix o_ia_p = {
 864                                         .type = htons(DHCPV6_OPT_IA_PREFIX),
 865                                         .len = htons(sizeof(o_ia_p) - 4),
 866                                         .preferred = htonl(prefix_pref),
 867                                         .valid = htonl(prefix_valid),
 868                                         .prefix = (a->managed_size) ? addrs[i].prefix : a->length,
 869                                         .addr = addrs[i].addr.in6,
 870                                 };
 871
 872                                 o_ia_p.addr.s6_addr32[1] |= htonl(a->assigned);
 873                                 o_ia_p.addr.s6_addr32[2] = o_ia_p.addr.s6_addr32[3] = 0;
 874
 875                                 if ((a->assigned == 0 && a->managed_size == 0) ||
 876                                                 !valid_prefix_length(a, addrs[i].prefix))
 877                                         continue;
 878
 879                                 if (buflen < ia_len + sizeof(o_ia_p))
 880                                         return 0;
 881
 882                                 memcpy(buf + ia_len, &o_ia_p, sizeof(o_ia_p));
 883                                 ia_len += sizeof(o_ia_p);
 884                         } else {
 885                                 struct dhcpv6_ia_addr o_ia_a = {
 886                                         .type = htons(DHCPV6_OPT_IA_ADDR),
 887                                         .len = htons(sizeof(o_ia_a) - 4),
 888                                         .addr = addrs[i].addr.in6,
 889                                         .preferred = htonl(prefix_pref),
 890                                         .valid = htonl(prefix_valid)
 891                                 };
 892
 893                                 o_ia_a.addr.s6_addr32[3] = htonl(a->assigned);
 894
 895                                 if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) ||
 896                                                 a->assigned == 0)
 897                                         continue;
 898
 899                                 if (buflen < ia_len + sizeof(o_ia_a))
 900                                         return 0;
 901
 902                                 memcpy(buf + ia_len, &o_ia_a, sizeof(o_ia_a));
 903                                 ia_len += sizeof(o_ia_a);
 904                         }
 905
 906                         /* Calculate T1 / T2 based on non-deprecated addresses */
 907                         if (prefix_pref > 0) {
 908                                 if (prefix_pref < pref)
 909                                         pref = prefix_pref;
 910
 911                                 if (prefix_valid < valid)
 912                                         valid = prefix_valid;
 913                         }
 914                 }
 915
 916                 if (!INFINITE_VALID(a->valid_until))
 917                         /* UINT32_MAX is considered as infinite leasetime */
 918                         a->valid_until = (valid == UINT32_MAX) ? 0 : valid + now;
 919
 920                 o_ia.t1 = htonl((pref == UINT32_MAX) ? pref : pref * 5 / 10);
 921                 o_ia.t2 = htonl((pref == UINT32_MAX) ? pref : pref * 8 / 10);
 922
 923                 if (!o_ia.t1)
 924                         o_ia.t1 = htonl(1);
 925
 926                 if (!o_ia.t2)
 927                         o_ia.t2 = htonl(1);
 928         }
 929
 930         if (!request) {
 931                 uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
 932                 uint16_t otype, olen;
 933
 934                 dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
 935                         struct dhcpv6_ia_prefix *ia_p = (struct dhcpv6_ia_prefix *)&odata[-4];
 936                         struct dhcpv6_ia_addr *ia_a = (struct dhcpv6_ia_addr *)&odata[-4];
 937                         bool found = false;
 938
 939                         if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*ia_p) - 4) &&
 940                                         (otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*ia_a) - 4))
 941                                 continue;
 942
 943                         if (a) {
 944                                 struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
 945                                 size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->addr6_len;
 946
 947                                 for (size_t i = 0; i < addrlen; ++i) {
 948                                         if (!valid_addr(&addrs[i], now))
 949                                                 continue;
 950
 951                                         struct in6_addr addr = addrs[i].addr.in6;
 952                                         if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
 953                                                 addr.s6_addr32[1] |= htonl(a->assigned);
 954                                                 addr.s6_addr32[2] = addr.s6_addr32[3] = 0;
 955
 956                                                 if (!memcmp(&ia_p->addr, &addr, sizeof(addr)) &&
 957                                                                 ia_p->prefix == ((a->managed) ? addrs[i].prefix : a->length))
 958                                                         found = true;
 959                                         } else {
 960                                                 addr.s6_addr32[3] = htonl(a->assigned);
 961
 962                                                 if (!memcmp(&ia_a->addr, &addr, sizeof(addr)))
 963                                                         found = true;
 964                                         }
 965                                 }
 966                         }
 967
 968                         if (!found) {
 969                                 if (otype == DHCPV6_OPT_IA_PREFIX) {
 970                                         struct dhcpv6_ia_prefix o_ia_p = {
 971                                                 .type = htons(DHCPV6_OPT_IA_PREFIX),
 972                                                 .len = htons(sizeof(o_ia_p) - 4),
 973                                                 .preferred = 0,
 974                                                 .valid = 0,
 975                                                 .prefix = ia_p->prefix,
 976                                                 .addr = ia_p->addr,
 977                                         };
 978
 979                                         if (buflen < ia_len + sizeof(o_ia_p))
 980                                                 return 0;
 981
 982                                         memcpy(buf + ia_len, &o_ia_p, sizeof(o_ia_p));
 983                                         ia_len += sizeof(o_ia_p);
 984                                 } else {
 985                                         struct dhcpv6_ia_addr o_ia_a = {
 986                                                 .type = htons(DHCPV6_OPT_IA_ADDR),
 987                                                 .len = htons(sizeof(o_ia_a) - 4),
 988                                                 .addr = ia_a->addr,
 989                                                 .preferred = 0,
 990                                                 .valid = 0,
 991                                         };
 992
 993                                         if (buflen < ia_len + sizeof(o_ia_a))
 994                                                 continue;
 995
 996                                         memcpy(buf + ia_len, &o_ia_a, sizeof(o_ia_a));
 997                                         ia_len += sizeof(o_ia_a);
 998                                 }
 999                         }
1000                 }
1001         }
1002
1003         o_ia.len = htons(ia_len - 4);
1004         memcpy(buf, &o_ia, sizeof(o_ia));
1005         return ia_len;
1006 }
1007
1008 struct log_ctxt {
1009         char *buf;
1010         int buf_len;
1011         int buf_idx;
1012 };
1013
1014 static void dhcpv6_log_ia_addr(struct in6_addr *addr, int prefix, _unused uint32_t pref,
1015                                 _unused uint32_t valid, void *arg)
1016 {
1017         struct log_ctxt *ctxt = (struct log_ctxt *)arg;
1018         char addrbuf[INET6_ADDRSTRLEN];
1019
1020         inet_ntop(AF_INET6, addr, addrbuf, sizeof(addrbuf));
1021         ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx, ctxt->buf_len - ctxt->buf_idx,
1022                                         "%s/%d ", addrbuf, prefix);
1023 }
1024
1025 static void dhcpv6_log(uint8_t msgtype, struct interface *iface, time_t now,
1026                 const char *duidbuf, bool is_pd, struct dhcp_assignment *a, int code)
1027 {
1028         const char *type = "UNKNOWN";
1029         const char *status = "UNKNOWN";
1030
1031         switch (msgtype) {
1032         case DHCPV6_MSG_SOLICIT:
1033                 type = "SOLICIT";
1034                 break;
1035         case DHCPV6_MSG_REQUEST:
1036                 type = "REQUEST";
1037                 break;
1038         case DHCPV6_MSG_CONFIRM:
1039                 type = "CONFIRM";
1040                 break;
1041         case DHCPV6_MSG_RENEW:
1042                 type = "RENEW";
1043                 break;
1044         case DHCPV6_MSG_REBIND:
1045                 type = "REBIND";
1046                 break;
1047         case DHCPV6_MSG_RELEASE:
1048                 type = "RELEASE";
1049                 break;
1050         case DHCPV6_MSG_DECLINE:
1051                 type = "DECLINE";
1052                 break;
1053         }
1054
1055         switch (code) {
1056         case DHCPV6_STATUS_OK:
1057                 status = "ok";
1058                 break;
1059         case DHCPV6_STATUS_NOADDRSAVAIL:
1060                 status = "no addresses available";
1061                 break;
1062         case DHCPV6_STATUS_NOBINDING:
1063                 status = "no binding";
1064                 break;
1065         case DHCPV6_STATUS_NOTONLINK:
1066                 status = "not on-link";
1067                 break;
1068         case DHCPV6_STATUS_NOPREFIXAVAIL:
1069                 status = "no prefix available";
1070                 break;
1071         }
1072
1073         char leasebuf[256] = "";
1074
1075         if (a) {
1076                 struct log_ctxt ctxt = {.buf = leasebuf,
1077                                         .buf_len = sizeof(leasebuf),
1078                                         .buf_idx = 0 };
1079
1080                 dhcpv6_ia_enum_addrs(iface, a, now, dhcpv6_log_ia_addr, &ctxt);
1081         }
1082
1083         syslog(LOG_WARNING, "DHCPV6 %s %s from %s on %s: %s %s", type, (is_pd) ? "IA_PD" : "IA_NA",
1084                         duidbuf, iface->name, status, leasebuf);
1085 }
1086
1087 static bool dhcpv6_ia_on_link(const struct dhcpv6_ia_hdr *ia, struct dhcp_assignment *a,
1088                 struct interface *iface)
1089 {
1090         struct odhcpd_ipaddr *addrs = (a && a->managed) ? a->managed : iface->addr6;
1091         size_t addrlen = (a && a->managed) ? (size_t)a->managed_size : iface->addr6_len;
1092         time_t now = odhcpd_time();
1093         uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
1094         uint16_t otype, olen;
1095         bool onlink = true;
1096
1097         dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
1098                 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix *)&odata[-4];
1099                 struct dhcpv6_ia_addr *n = (struct dhcpv6_ia_addr *)&odata[-4];
1100
1101                 if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*p) - 4) &&
1102                                 (otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*n) - 4))
1103                         continue;
1104
1105                 onlink = false;
1106                 for (size_t i = 0; i < addrlen; ++i) {
1107                         if (!valid_addr(&addrs[i], now))
1108                                 continue;
1109
1110                         if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
1111                                 if (p->prefix < addrs[i].prefix ||
1112                                     odhcpd_bmemcmp(&p->addr, &addrs[i].addr.in6, addrs[i].prefix))
1113                                         continue;
1114
1115                         } else if (odhcpd_bmemcmp(&n->addr, &addrs[i].addr.in6, addrs[i].prefix))
1116                                 continue;
1117
1118                         onlink = true;
1119                 }
1120
1121                 if (!onlink)
1122                         break;
1123         }
1124
1125         return onlink;
1126 }
1127
1128 ssize_t dhcpv6_ia_handle_IAs(uint8_t *buf, size_t buflen, struct interface *iface,
1129                 const struct sockaddr_in6 *addr, const void *data, const uint8_t *end)
1130 {
1131         struct lease *l;
1132         struct dhcp_assignment *first = NULL;
1133         const struct dhcpv6_client_header *hdr = data;
1134         time_t now = odhcpd_time();
1135         uint16_t otype, olen, clid_len = 0;
1136         uint8_t *start = (uint8_t *)&hdr[1], *odata;
1137         uint8_t *clid_data = NULL, mac[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
1138         size_t hostname_len = 0, response_len = 0;
1139         bool notonlink = false, rapid_commit = false, accept_reconf = false;
1140         char duidbuf[261], hostname[256];
1141
1142         dhcpv6_for_each_option(start, end, otype, olen, odata) {
1143                 if (otype == DHCPV6_OPT_CLIENTID) {
1144                         clid_data = odata;
1145                         clid_len = olen;
1146
1147                         if (olen == 14 && odata[0] == 0 && odata[1] == 1)
1148                                 memcpy(mac, &odata[8], sizeof(mac));
1149                         else if (olen == 10 && odata[0] == 0 && odata[1] == 3)
1150                                 memcpy(mac, &odata[4], sizeof(mac));
1151
1152                         if (olen <= 130)
1153                                 odhcpd_hexlify(duidbuf, odata, olen);
1154                 } else if (otype == DHCPV6_OPT_FQDN && olen >= 2 && olen <= 255) {
1155                         uint8_t fqdn_buf[256];
1156                         memcpy(fqdn_buf, odata, olen);
1157                         fqdn_buf[olen++] = 0;
1158
1159                         if (dn_expand(&fqdn_buf[1], &fqdn_buf[olen], &fqdn_buf[1], hostname, sizeof(hostname)) > 0)
1160                                 hostname_len = strcspn(hostname, ".");
1161                 } else if (otype == DHCPV6_OPT_RECONF_ACCEPT)
1162                         accept_reconf = true;
1163                 else if (otype == DHCPV6_OPT_RAPID_COMMIT && hdr->msg_type == DHCPV6_MSG_SOLICIT)
1164                         rapid_commit = true;
1165         }
1166
1167         if (!clid_data || !clid_len || clid_len > 130)
1168                 goto out;
1169
1170         l = config_find_lease_by_duid(clid_data, clid_len);
1171         if (!l)
1172                 l = config_find_lease_by_mac(mac);
1173
1174         dhcpv6_for_each_option(start, end, otype, olen, odata) {
1175                 bool is_pd = (otype == DHCPV6_OPT_IA_PD);
1176                 bool is_na = (otype == DHCPV6_OPT_IA_NA);
1177                 bool ia_addr_present = false;
1178                 if (!is_pd && !is_na)
1179                         continue;
1180
1181                 struct dhcpv6_ia_hdr *ia = (struct dhcpv6_ia_hdr*)&odata[-4];
1182                 size_t ia_response_len = 0;
1183                 uint8_t reqlen = (is_pd) ? 62 : 128;
1184                 uint32_t reqhint = 0;
1185
1186                 /* Parse request hint for IA-PD */
1187                 if (is_pd) {
1188                         uint8_t *sdata;
1189                         uint16_t stype, slen;
1190                         dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1191                                 if (stype != DHCPV6_OPT_IA_PREFIX || slen < sizeof(struct dhcpv6_ia_prefix) - 4)
1192                                         continue;
1193
1194                                 struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&sdata[-4];
1195                                 if (p->prefix) {
1196                                         reqlen = p->prefix;
1197                                         reqhint = ntohl(p->addr.s6_addr32[1]);
1198                                         if (reqlen > 32 && reqlen <= 64)
1199                                                 reqhint &= (1U << (64 - reqlen)) - 1;
1200                                 }
1201                         }
1202
1203                         if (reqlen > 64)
1204                                 reqlen = 64;
1205                 } else if (is_na) {
1206                         uint8_t *sdata;
1207                         uint16_t stype, slen;
1208                         dhcpv6_for_each_option(&ia[1], odata + olen, stype, slen, sdata) {
1209                                 if (stype != DHCPV6_OPT_IA_ADDR || slen < sizeof(struct dhcpv6_ia_addr) - 4)
1210                                         continue;
1211
1212                                 ia_addr_present = true;
1213                         }
1214                 }
1215
1216                 /* Find assignment */
1217                 struct dhcp_assignment *c, *a = NULL;
1218                 list_for_each_entry(c, &iface->ia_assignments, head) {
1219                         if ((c->clid_len == clid_len && !memcmp(c->clid_data, clid_data, clid_len)) &&
1220                             c->iaid == ia->iaid && (INFINITE_VALID(c->valid_until) || now < c->valid_until) &&
1221                             ((is_pd && c->length <= 64) || (is_na && c->length == 128))) {
1222                                 a = c;
1223
1224                                 /* Reset state */
1225                                 if (a->flags & OAF_BOUND)
1226                                         apply_lease(iface, a, false);
1227
1228                                 stop_reconf(a);
1229                                 break;
1230                         }
1231                 }
1232
1233                 if (l && a && a->lease != l) {
1234                         dhcpv6_ia_free_assignment(a);
1235                         a = NULL;
1236                 }
1237
1238                 /* Generic message handling */
1239                 uint16_t status = DHCPV6_STATUS_OK;
1240                 if (a && a->managed_size < 0)
1241                         return -1;
1242
1243                 if (hdr->msg_type == DHCPV6_MSG_SOLICIT ||
1244                                 hdr->msg_type == DHCPV6_MSG_REQUEST ||
1245                                 (hdr->msg_type == DHCPV6_MSG_REBIND && !a)) {
1246                         bool assigned = !!a;
1247
1248                         if (!a) {
1249                                 if ((!iface->no_dynamic_dhcp || (l && is_na)) &&
1250                                     (iface->dhcpv6_pd || iface->dhcpv6_na)) {
1251                                         /* Create new binding */
1252                                         a = calloc(1, sizeof(*a) + clid_len);
1253
1254                                         if (a) {
1255                                                 a->clid_len = clid_len;
1256                                                 memcpy(a->clid_data, clid_data, clid_len);
1257                                                 a->iaid = ia->iaid;
1258                                                 a->length = reqlen;
1259                                                 a->peer = *addr;
1260                                                 a->assigned = is_na && l ? l->hostid : reqhint;
1261                                                 /* Set valid time to 0 for static lease indicating */
1262                                                 /* infinite lifetime otherwise current time        */
1263                                                 a->valid_until = l ? 0 : now;
1264                                                 a->iface = iface;
1265                                                 a->flags = OAF_DHCPV6;
1266
1267                                                 if (first)
1268                                                         memcpy(a->key, first->key, sizeof(a->key));
1269                                                 else
1270                                                         odhcpd_urandom(a->key, sizeof(a->key));
1271
1272                                                 if (is_pd && iface->dhcpv6_pd)
1273                                                         while (!(assigned = assign_pd(iface, a)) &&
1274                                                                !a->managed_size && ++a->length <= 64);
1275                                                 else if (is_na && iface->dhcpv6_na)
1276                                                         assigned = assign_na(iface, a);
1277
1278                                                 if (l && assigned) {
1279                                                         a->flags |= OAF_STATIC;
1280
1281                                                         if (l->hostname)
1282                                                                 a->hostname = strdup(l->hostname);
1283
1284                                                         if (l->leasetime)
1285                                                                 a->leasetime = l->leasetime;
1286
1287                                                         list_add(&a->lease_list, &l->assignments);
1288                                                         a->lease = l;
1289                                                 }
1290
1291                                                 if (a->managed_size && !assigned)
1292                                                         return -1;
1293                                         }
1294                                 }
1295                         }
1296
1297                         if (!assigned || iface->addr6_len == 0)
1298                                 /* Set error status */
1299                                 status = (is_pd) ? DHCPV6_STATUS_NOPREFIXAVAIL : DHCPV6_STATUS_NOADDRSAVAIL;
1300                         else if (hdr->msg_type == DHCPV6_MSG_REQUEST && !dhcpv6_ia_on_link(ia, a, iface)) {
1301                                 /* Send NOTONLINK staus for the IA */
1302                                 status = DHCPV6_STATUS_NOTONLINK;
1303                                 assigned = false;
1304                         } else if (accept_reconf && assigned && !first &&
1305                                         hdr->msg_type != DHCPV6_MSG_REBIND) {
1306                                 size_t handshake_len = 4;
1307                                 buf[0] = 0;
1308                                 buf[1] = DHCPV6_OPT_RECONF_ACCEPT;
1309                                 buf[2] = 0;
1310                                 buf[3] = 0;
1311
1312                                 if (hdr->msg_type == DHCPV6_MSG_REQUEST) {
1313                                         struct dhcpv6_auth_reconfigure auth = {
1314                                                 htons(DHCPV6_OPT_AUTH),
1315                                                 htons(sizeof(auth) - 4),
1316                                                 3, 1, 0,
1317                                                 {htonl(time(NULL)), htonl(++serial)},
1318                                                 1,
1319                                                 {0}
1320                                         };
1321                                         memcpy(auth.key, a->key, sizeof(a->key));
1322                                         memcpy(buf + handshake_len, &auth, sizeof(auth));
1323                                         handshake_len += sizeof(auth);
1324                                 }
1325
1326
1327                                 buf += handshake_len;
1328                                 buflen -= handshake_len;
1329                                 response_len += handshake_len;
1330
1331                                 first = a;
1332                         }
1333
1334                         ia_response_len = build_ia(buf, buflen, status, ia, a, iface,
1335                                                         hdr->msg_type == DHCPV6_MSG_REBIND ? false : true);
1336
1337                         /* Was only a solicitation: mark binding for removal */
1338                         if (assigned && hdr->msg_type == DHCPV6_MSG_SOLICIT && !rapid_commit) {
1339                                 a->flags &= ~OAF_BOUND;
1340                                 a->flags |= OAF_TENTATIVE;
1341
1342                                 if (!(a->flags & OAF_STATIC))
1343                                         /* Keep tentative assignment around for 60 seconds */
1344                                         a->valid_until = now + 60;
1345
1346                         } else if (assigned &&
1347                                    ((hdr->msg_type == DHCPV6_MSG_SOLICIT && rapid_commit) ||
1348                                     hdr->msg_type == DHCPV6_MSG_REQUEST ||
1349                                     hdr->msg_type == DHCPV6_MSG_REBIND)) {
1350                                 if ((!(a->flags & OAF_STATIC) || !a->hostname) && hostname_len > 0) {
1351                                         a->hostname = realloc(a->hostname, hostname_len + 1);
1352                                         if (a->hostname) {
1353                                                 memcpy(a->hostname, hostname, hostname_len);
1354                                                 a->hostname[hostname_len] = 0;
1355
1356                                                 if (odhcpd_valid_hostname(a->hostname))
1357                                                         a->flags &= ~OAF_BROKEN_HOSTNAME;
1358                                                 else
1359                                                         a->flags |= OAF_BROKEN_HOSTNAME;
1360                                         }
1361                                 }
1362                                 a->accept_reconf = accept_reconf;
1363                                 a->flags &= ~OAF_TENTATIVE;
1364                                 a->flags |= OAF_BOUND;
1365                                 apply_lease(iface, a, true);
1366                         } else if (!assigned && a && a->managed_size == 0) {
1367                                 /* Cleanup failed assignment */
1368                                 dhcpv6_ia_free_assignment(a);
1369                                 a = NULL;
1370                         }
1371                 } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1372                                 hdr->msg_type == DHCPV6_MSG_RELEASE ||
1373                                 hdr->msg_type == DHCPV6_MSG_REBIND ||
1374                                 hdr->msg_type == DHCPV6_MSG_DECLINE) {
1375                         if (!a && hdr->msg_type != DHCPV6_MSG_REBIND) {
1376                                 status = DHCPV6_STATUS_NOBINDING;
1377                                 ia_response_len = build_ia(buf, buflen, status, ia, a, iface, false);
1378                         } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
1379                                         hdr->msg_type == DHCPV6_MSG_REBIND) {
1380                                 ia_response_len = build_ia(buf, buflen, status, ia, a, iface, false);
1381                                 if (a) {
1382                                         a->flags |= OAF_BOUND;
1383                                         apply_lease(iface, a, true);
1384                                 }
1385                         } else if (hdr->msg_type == DHCPV6_MSG_RELEASE) {
1386                                 if (!(a->flags & OAF_STATIC))
1387                                         a->valid_until = now - 1;
1388
1389                                 if (a->flags & OAF_BOUND) {
1390                                         apply_lease(iface, a, false);
1391                                         a->flags &= ~OAF_BOUND;
1392                                 }
1393                         } else if (hdr->msg_type == DHCPV6_MSG_DECLINE && a->length == 128) {
1394                                 a->flags &= ~OAF_BOUND;
1395
1396                                 if (!(a->flags & OAF_STATIC)) {
1397                                         a->clid_len = 0;
1398                                         a->valid_until = now + 3600; /* Block address for 1h */
1399                                 }
1400                         }
1401                 } else if (hdr->msg_type == DHCPV6_MSG_CONFIRM) {
1402                         if (ia_addr_present && !dhcpv6_ia_on_link(ia, a, iface)) {
1403                                 notonlink = true;
1404                                 break;
1405                         }
1406
1407                         if (!ia_addr_present || !a || !(a->flags & OAF_BOUND)) {
1408                                 response_len = 0;
1409                                 goto out;
1410                         }
1411                 }
1412
1413                 buf += ia_response_len;
1414                 buflen -= ia_response_len;
1415                 response_len += ia_response_len;
1416                 dhcpv6_log(hdr->msg_type, iface, now, duidbuf, is_pd, a, status);
1417         }
1418
1419         switch (hdr->msg_type) {
1420         case DHCPV6_MSG_RELEASE:
1421         case DHCPV6_MSG_DECLINE:
1422         case DHCPV6_MSG_CONFIRM:
1423                 if (response_len + 6 < buflen) {
1424                         buf[0] = 0;
1425                         buf[1] = DHCPV6_OPT_STATUS;
1426                         buf[2] = 0;
1427                         buf[3] = 2;
1428                         buf[4] = 0;
1429                         buf[5] = (notonlink) ? DHCPV6_STATUS_NOTONLINK : DHCPV6_STATUS_OK;
1430                         response_len += 6;
1431                 }
1432                 break;
1433
1434         default:
1435                 break;
1436         }
1437
1438         dhcpv6_ia_write_statefile();
1439
1440 out:
1441         return response_len;
1442 }