sbin/dhclient/clparse.c

   1 /*      $OpenBSD: clparse.c,v 1.18 2004/09/15 18:15:18 henning Exp $    */
   2
   3 /* Parser for dhclient config and lease files... */
   4
   5 /*-
   6  * SPDX-License-Identifier: BSD-3-Clause
   7  *
   8  * Copyright (c) 1997 The Internet Software Consortium.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  *
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. Neither the name of The Internet Software Consortium nor the names
  21  *    of its contributors may be used to endorse or promote products derived
  22  *    from this software without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
  25  * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  26  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  27  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  28  * DISCLAIMED.  IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
  29  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  31  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  32  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  33  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  34  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  35  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  * This software has been written for the Internet Software Consortium
  39  * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
  40  * Enterprises.  To learn more about the Internet Software Consortium,
  41  * see ``http://www.vix.com/isc''.  To learn more about Vixie
  42  * Enterprises, see ``http://www.vix.com''.
  43  */
  44
  45 #include <sys/cdefs.h>
  46 __FBSDID("$FreeBSD$");
  47
  48 #include "dhcpd.h"
  49 #include "dhctoken.h"
  50
  51 struct client_config top_level_config;
  52 struct interface_info *dummy_interfaces;
  53 extern struct interface_info *ifi;
  54
  55 char client_script_name[] = "/sbin/dhclient-script";
  56
  57 /*
  58  * client-conf-file :== client-declarations EOF
  59  * client-declarations :== <nil>
  60  *                       | client-declaration
  61  *                       | client-declarations client-declaration
  62  */
  63 int
  64 read_client_conf(void)
  65 {
  66         FILE                    *cfile;
  67         char                    *val;
  68         int                      token;
  69         struct client_config    *config;
  70
  71         new_parse(path_dhclient_conf);
  72
  73         /* Set up the initial dhcp option universe. */
  74         initialize_universes();
  75
  76         /* Initialize the top level client configuration. */
  77         memset(&top_level_config, 0, sizeof(top_level_config));
  78
  79         /* Set some defaults... */
  80         top_level_config.timeout = 60;
  81         top_level_config.select_interval = 0;
  82         top_level_config.reboot_timeout = 10;
  83         top_level_config.retry_interval = 300;
  84         top_level_config.backoff_cutoff = 15;
  85         top_level_config.initial_interval = 3;
  86         top_level_config.bootp_policy = ACCEPT;
  87         top_level_config.script_name = client_script_name;
  88         top_level_config.requested_options
  89             [top_level_config.requested_option_count++] = DHO_SUBNET_MASK;
  90         top_level_config.requested_options
  91             [top_level_config.requested_option_count++] = DHO_BROADCAST_ADDRESS;
  92         top_level_config.requested_options
  93             [top_level_config.requested_option_count++] = DHO_TIME_OFFSET;
  94         top_level_config.requested_options
  95             [top_level_config.requested_option_count++] = DHO_CLASSLESS_ROUTES;
  96         top_level_config.requested_options
  97             [top_level_config.requested_option_count++] = DHO_ROUTERS;
  98         top_level_config.requested_options
  99             [top_level_config.requested_option_count++] = DHO_DOMAIN_NAME;
 100         top_level_config.requested_options
 101             [top_level_config.requested_option_count++] =
 102             DHO_DOMAIN_NAME_SERVERS;
 103         top_level_config.requested_options
 104             [top_level_config.requested_option_count++] = DHO_HOST_NAME;
 105         top_level_config.requested_options
 106             [top_level_config.requested_option_count++] = DHO_DOMAIN_SEARCH;
 107         top_level_config.requested_options
 108             [top_level_config.requested_option_count++] = DHO_INTERFACE_MTU;
 109
 110         if ((cfile = fopen(path_dhclient_conf, "r")) != NULL) {
 111                 do {
 112                         token = peek_token(&val, cfile);
 113                         if (token == EOF)
 114                                 break;
 115                         parse_client_statement(cfile, NULL, &top_level_config);
 116                 } while (1);
 117                 token = next_token(&val, cfile); /* Clear the peek buffer */
 118                 fclose(cfile);
 119         }
 120
 121         /*
 122          * Set up state and config structures for clients that don't
 123          * have per-interface configuration declarations.
 124          */
 125         config = NULL;
 126         if (!ifi->client) {
 127                 ifi->client = malloc(sizeof(struct client_state));
 128                 if (!ifi->client)
 129                         error("no memory for client state.");
 130                 memset(ifi->client, 0, sizeof(*(ifi->client)));
 131         }
 132         if (!ifi->client->config) {
 133                 if (!config) {
 134                         config = malloc(sizeof(struct client_config));
 135                         if (!config)
 136                                 error("no memory for client config.");
 137                         memcpy(config, &top_level_config,
 138                                 sizeof(top_level_config));
 139                 }
 140                 ifi->client->config = config;
 141         }
 142
 143         return (!warnings_occurred);
 144 }
 145
 146 /*
 147  * lease-file :== client-lease-statements EOF
 148  * client-lease-statements :== <nil>
 149  *                   | client-lease-statements LEASE client-lease-statement
 150  */
 151 void
 152 read_client_leases(void)
 153 {
 154         FILE    *cfile;
 155         char    *val;
 156         int      token;
 157
 158         new_parse(path_dhclient_db);
 159
 160         /* Open the lease file.   If we can't open it, just return -
 161            we can safely trust the server to remember our state. */
 162         if ((cfile = fopen(path_dhclient_db, "r")) == NULL)
 163                 return;
 164         do {
 165                 token = next_token(&val, cfile);
 166                 if (token == EOF)
 167                         break;
 168                 if (token != LEASE) {
 169                         warning("Corrupt lease file - possible data loss!");
 170                         skip_to_semi(cfile);
 171                         break;
 172                 } else
 173                         parse_client_lease_statement(cfile, 0);
 174
 175         } while (1);
 176         fclose(cfile);
 177 }
 178
 179 /*
 180  * client-declaration :==
 181  *      SEND option-decl |
 182  *      DEFAULT option-decl |
 183  *      SUPERSEDE option-decl |
 184  *      PREPEND option-decl |
 185  *      APPEND option-decl |
 186  *      hardware-declaration |
 187  *      REQUEST option-list |
 188  *      REQUIRE option-list |
 189  *      TIMEOUT number |
 190  *      RETRY number |
 191  *      REBOOT number |
 192  *      SELECT_TIMEOUT number |
 193  *      SCRIPT string |
 194  *      interface-declaration |
 195  *      LEASE client-lease-statement |
 196  *      ALIAS client-lease-statement
 197  */
 198 void
 199 parse_client_statement(FILE *cfile, struct interface_info *ip,
 200     struct client_config *config)
 201 {
 202         int              token;
 203         char            *val;
 204         struct option   *option;
 205
 206         switch (next_token(&val, cfile)) {
 207         case SEND:
 208                 parse_option_decl(cfile, &config->send_options[0]);
 209                 return;
 210         case DEFAULT:
 211                 option = parse_option_decl(cfile, &config->defaults[0]);
 212                 if (option)
 213                         config->default_actions[option->code] = ACTION_DEFAULT;
 214                 return;
 215         case SUPERSEDE:
 216                 option = parse_option_decl(cfile, &config->defaults[0]);
 217                 if (option)
 218                         config->default_actions[option->code] =
 219                             ACTION_SUPERSEDE;
 220                 return;
 221         case APPEND:
 222                 option = parse_option_decl(cfile, &config->defaults[0]);
 223                 if (option)
 224                         config->default_actions[option->code] = ACTION_APPEND;
 225                 return;
 226         case PREPEND:
 227                 option = parse_option_decl(cfile, &config->defaults[0]);
 228                 if (option)
 229                         config->default_actions[option->code] = ACTION_PREPEND;
 230                 return;
 231         case MEDIA:
 232                 parse_string_list(cfile, &config->media, 1);
 233                 return;
 234         case HARDWARE:
 235                 if (ip)
 236                         parse_hardware_param(cfile, &ip->hw_address);
 237                 else {
 238                         parse_warn("hardware address parameter %s",
 239                                     "not allowed here.");
 240                         skip_to_semi(cfile);
 241                 }
 242                 return;
 243         case REQUEST:
 244                 config->requested_option_count =
 245                         parse_option_list(cfile, config->requested_options);
 246                 return;
 247         case REQUIRE:
 248                 memset(config->required_options, 0,
 249                     sizeof(config->required_options));
 250                 parse_option_list(cfile, config->required_options);
 251                 return;
 252         case TIMEOUT:
 253                 parse_lease_time(cfile, &config->timeout);
 254                 return;
 255         case RETRY:
 256                 parse_lease_time(cfile, &config->retry_interval);
 257                 return;
 258         case SELECT_TIMEOUT:
 259                 parse_lease_time(cfile, &config->select_interval);
 260                 return;
 261         case REBOOT:
 262                 parse_lease_time(cfile, &config->reboot_timeout);
 263                 return;
 264         case BACKOFF_CUTOFF:
 265                 parse_lease_time(cfile, &config->backoff_cutoff);
 266                 return;
 267         case INITIAL_INTERVAL:
 268                 parse_lease_time(cfile, &config->initial_interval);
 269                 return;
 270         case SCRIPT:
 271                 config->script_name = parse_string(cfile);
 272                 return;
 273         case INTERFACE:
 274                 if (ip)
 275                         parse_warn("nested interface declaration.");
 276                 parse_interface_declaration(cfile, config);
 277                 return;
 278         case LEASE:
 279                 parse_client_lease_statement(cfile, 1);
 280                 return;
 281         case ALIAS:
 282                 parse_client_lease_statement(cfile, 2);
 283                 return;
 284         case REJECT:
 285                 parse_reject_statement(cfile, config);
 286                 return;
 287         default:
 288                 parse_warn("expecting a statement.");
 289                 skip_to_semi(cfile);
 290                 break;
 291         }
 292         token = next_token(&val, cfile);
 293         if (token != SEMI) {
 294                 parse_warn("semicolon expected.");
 295                 skip_to_semi(cfile);
 296         }
 297 }
 298
 299 unsigned
 300 parse_X(FILE *cfile, u_int8_t *buf, unsigned max)
 301 {
 302         int      token;
 303         char    *val;
 304         unsigned len;
 305
 306         token = peek_token(&val, cfile);
 307         if (token == NUMBER_OR_NAME || token == NUMBER) {
 308                 len = 0;
 309                 do {
 310                         token = next_token(&val, cfile);
 311                         if (token != NUMBER && token != NUMBER_OR_NAME) {
 312                                 parse_warn("expecting hexadecimal constant.");
 313                                 skip_to_semi(cfile);
 314                                 return (0);
 315                         }
 316                         convert_num(&buf[len], val, 16, 8);
 317                         if (len++ > max) {
 318                                 parse_warn("hexadecimal constant too long.");
 319                                 skip_to_semi(cfile);
 320                                 return (0);
 321                         }
 322                         token = peek_token(&val, cfile);
 323                         if (token == COLON)
 324                                 token = next_token(&val, cfile);
 325                 } while (token == COLON);
 326                 val = (char *)buf;
 327         } else if (token == STRING) {
 328                 token = next_token(&val, cfile);
 329                 len = strlen(val);
 330                 if (len + 1 > max) {
 331                         parse_warn("string constant too long.");
 332                         skip_to_semi(cfile);
 333                         return (0);
 334                 }
 335                 memcpy(buf, val, len + 1);
 336         } else {
 337                 parse_warn("expecting string or hexadecimal data");
 338                 skip_to_semi(cfile);
 339                 return (0);
 340         }
 341         return (len);
 342 }
 343
 344 /*
 345  * option-list :== option_name |
 346  *                 option_list COMMA option_name
 347  */
 348 int
 349 parse_option_list(FILE *cfile, u_int8_t *list)
 350 {
 351         int      ix, i;
 352         int      token;
 353         char    *val;
 354
 355         ix = 0;
 356         do {
 357                 token = next_token(&val, cfile);
 358                 if (!is_identifier(token)) {
 359                         parse_warn("expected option name.");
 360                         skip_to_semi(cfile);
 361                         return (0);
 362                 }
 363                 for (i = 0; i < 256; i++)
 364                         if (!strcasecmp(dhcp_options[i].name, val))
 365                                 break;
 366
 367                 if (i == 256) {
 368                         parse_warn("%s: unexpected option name.", val);
 369                         skip_to_semi(cfile);
 370                         return (0);
 371                 }
 372                 list[ix++] = i;
 373                 if (ix == 256) {
 374                         parse_warn("%s: too many options.", val);
 375                         skip_to_semi(cfile);
 376                         return (0);
 377                 }
 378                 token = next_token(&val, cfile);
 379         } while (token == COMMA);
 380         if (token != SEMI) {
 381                 parse_warn("expecting semicolon.");
 382                 skip_to_semi(cfile);
 383                 return (0);
 384         }
 385         return (ix);
 386 }
 387
 388 /*
 389  * interface-declaration :==
 390  *      INTERFACE string LBRACE client-declarations RBRACE
 391  */
 392 void
 393 parse_interface_declaration(FILE *cfile, struct client_config *outer_config)
 394 {
 395         int                      token;
 396         char                    *val;
 397         struct interface_info   *ip;
 398
 399         token = next_token(&val, cfile);
 400         if (token != STRING) {
 401                 parse_warn("expecting interface name (in quotes).");
 402                 skip_to_semi(cfile);
 403                 return;
 404         }
 405
 406         ip = interface_or_dummy(val);
 407
 408         if (!ip->client)
 409                 make_client_state(ip);
 410
 411         if (!ip->client->config)
 412                 make_client_config(ip, outer_config);
 413
 414         token = next_token(&val, cfile);
 415         if (token != LBRACE) {
 416                 parse_warn("expecting left brace.");
 417                 skip_to_semi(cfile);
 418                 return;
 419         }
 420
 421         do {
 422                 token = peek_token(&val, cfile);
 423                 if (token == EOF) {
 424                         parse_warn("unterminated interface declaration.");
 425                         return;
 426                 }
 427                 if (token == RBRACE)
 428                         break;
 429                 parse_client_statement(cfile, ip, ip->client->config);
 430         } while (1);
 431         token = next_token(&val, cfile);
 432 }
 433
 434 struct interface_info *
 435 interface_or_dummy(char *name)
 436 {
 437         struct interface_info   *ip;
 438
 439         /* Find the interface (if any) that matches the name. */
 440         if (!strcmp(ifi->name, name))
 441                 return (ifi);
 442
 443         /* If it's not a real interface, see if it's on the dummy list. */
 444         for (ip = dummy_interfaces; ip; ip = ip->next)
 445                 if (!strcmp(ip->name, name))
 446                         return (ip);
 447
 448         /*
 449          * If we didn't find an interface, make a dummy interface as a
 450          * placeholder.
 451          */
 452         ip = malloc(sizeof(*ip));
 453         if (!ip)
 454                 error("Insufficient memory to record interface %s", name);
 455         memset(ip, 0, sizeof(*ip));
 456         strlcpy(ip->name, name, IFNAMSIZ);
 457         ip->next = dummy_interfaces;
 458         dummy_interfaces = ip;
 459         return (ip);
 460 }
 461
 462 void
 463 make_client_state(struct interface_info *ip)
 464 {
 465         ip->client = malloc(sizeof(*(ip->client)));
 466         if (!ip->client)
 467                 error("no memory for state on %s", ip->name);
 468         memset(ip->client, 0, sizeof(*(ip->client)));
 469 }
 470
 471 void
 472 make_client_config(struct interface_info *ip, struct client_config *config)
 473 {
 474         ip->client->config = malloc(sizeof(struct client_config));
 475         if (!ip->client->config)
 476                 error("no memory for config for %s", ip->name);
 477         memset(ip->client->config, 0, sizeof(*(ip->client->config)));
 478         memcpy(ip->client->config, config, sizeof(*config));
 479 }
 480
 481 /*
 482  * client-lease-statement :==
 483  *      RBRACE client-lease-declarations LBRACE
 484  *
 485  *      client-lease-declarations :==
 486  *              <nil> |
 487  *              client-lease-declaration |
 488  *              client-lease-declarations client-lease-declaration
 489  */
 490 void
 491 parse_client_lease_statement(FILE *cfile, int is_static)
 492 {
 493         struct client_lease     *lease, *lp, *pl;
 494         struct interface_info   *ip;
 495         int                      token;
 496         char                    *val;
 497
 498         token = next_token(&val, cfile);
 499         if (token != LBRACE) {
 500                 parse_warn("expecting left brace.");
 501                 skip_to_semi(cfile);
 502                 return;
 503         }
 504
 505         lease = malloc(sizeof(struct client_lease));
 506         if (!lease)
 507                 error("no memory for lease.");
 508         memset(lease, 0, sizeof(*lease));
 509         lease->is_static = is_static;
 510
 511         ip = NULL;
 512
 513         do {
 514                 token = peek_token(&val, cfile);
 515                 if (token == EOF) {
 516                         parse_warn("unterminated lease declaration.");
 517                         free_client_lease(lease);
 518                         return;
 519                 }
 520                 if (token == RBRACE)
 521                         break;
 522                 parse_client_lease_declaration(cfile, lease, &ip);
 523         } while (1);
 524         token = next_token(&val, cfile);
 525
 526         /* If the lease declaration didn't include an interface
 527          * declaration that we recognized, it's of no use to us.
 528          */
 529         if (!ip) {
 530                 free_client_lease(lease);
 531                 return;
 532         }
 533
 534         /* Make sure there's a client state structure... */
 535         if (!ip->client)
 536                 make_client_state(ip);
 537
 538         /* If this is an alias lease, it doesn't need to be sorted in. */
 539         if (is_static == 2) {
 540                 ip->client->alias = lease;
 541                 return;
 542         }
 543
 544         /*
 545          * The new lease may supersede a lease that's not the active
 546          * lease but is still on the lease list, so scan the lease list
 547          * looking for a lease with the same address, and if we find it,
 548          * toss it.
 549          */
 550         pl = NULL;
 551         for (lp = ip->client->leases; lp; lp = lp->next) {
 552                 if (lp->address.len == lease->address.len &&
 553                     !memcmp(lp->address.iabuf, lease->address.iabuf,
 554                     lease->address.len)) {
 555                         if (pl)
 556                                 pl->next = lp->next;
 557                         else
 558                                 ip->client->leases = lp->next;
 559                         free_client_lease(lp);
 560                         break;
 561                 }
 562         }
 563
 564         /*
 565          * If this is a preloaded lease, just put it on the list of
 566          * recorded leases - don't make it the active lease.
 567          */
 568         if (is_static) {
 569                 lease->next = ip->client->leases;
 570                 ip->client->leases = lease;
 571                 return;
 572         }
 573
 574         /*
 575          * The last lease in the lease file on a particular interface is
 576          * the active lease for that interface.    Of course, we don't
 577          * know what the last lease in the file is until we've parsed
 578          * the whole file, so at this point, we assume that the lease we
 579          * just parsed is the active lease for its interface.   If
 580          * there's already an active lease for the interface, and this
 581          * lease is for the same ip address, then we just toss the old
 582          * active lease and replace it with this one.   If this lease is
 583          * for a different address, then if the old active lease has
 584          * expired, we dump it; if not, we put it on the list of leases
 585          * for this interface which are still valid but no longer
 586          * active.
 587          */
 588         if (ip->client->active) {
 589                 if (ip->client->active->expiry < cur_time)
 590                         free_client_lease(ip->client->active);
 591                 else if (ip->client->active->address.len ==
 592                     lease->address.len &&
 593                     !memcmp(ip->client->active->address.iabuf,
 594                     lease->address.iabuf, lease->address.len))
 595                         free_client_lease(ip->client->active);
 596                 else {
 597                         ip->client->active->next = ip->client->leases;
 598                         ip->client->leases = ip->client->active;
 599                 }
 600         }
 601         ip->client->active = lease;
 602
 603         /* Phew. */
 604 }
 605
 606 /*
 607  * client-lease-declaration :==
 608  *      BOOTP |
 609  *      INTERFACE string |
 610  *      FIXED_ADDR ip_address |
 611  *      FILENAME string |
 612  *      SERVER_NAME string |
 613  *      OPTION option-decl |
 614  *      RENEW time-decl |
 615  *      REBIND time-decl |
 616  *      EXPIRE time-decl
 617  */
 618 void
 619 parse_client_lease_declaration(FILE *cfile, struct client_lease *lease,
 620     struct interface_info **ipp)
 621 {
 622         int                      token;
 623         char                    *val;
 624         struct interface_info   *ip;
 625
 626         switch (next_token(&val, cfile)) {
 627         case BOOTP:
 628                 lease->is_bootp = 1;
 629                 break;
 630         case INTERFACE:
 631                 token = next_token(&val, cfile);
 632                 if (token != STRING) {
 633                         parse_warn("expecting interface name (in quotes).");
 634                         skip_to_semi(cfile);
 635                         break;
 636                 }
 637                 ip = interface_or_dummy(val);
 638                 *ipp = ip;
 639                 break;
 640         case FIXED_ADDR:
 641                 if (!parse_ip_addr(cfile, &lease->address))
 642                         return;
 643                 break;
 644         case MEDIUM:
 645                 parse_string_list(cfile, &lease->medium, 0);
 646                 return;
 647         case FILENAME:
 648                 lease->filename = parse_string(cfile);
 649                 return;
 650         case NEXT_SERVER:
 651                 if (!parse_ip_addr(cfile, &lease->nextserver))
 652                         return;
 653                 break;
 654         case SERVER_NAME:
 655                 lease->server_name = parse_string(cfile);
 656                 return;
 657         case RENEW:
 658                 lease->renewal = parse_date(cfile);
 659                 return;
 660         case REBIND:
 661                 lease->rebind = parse_date(cfile);
 662                 return;
 663         case EXPIRE:
 664                 lease->expiry = parse_date(cfile);
 665                 return;
 666         case OPTION:
 667                 parse_option_decl(cfile, lease->options);
 668                 return;
 669         default:
 670                 parse_warn("expecting lease declaration.");
 671                 skip_to_semi(cfile);
 672                 break;
 673         }
 674         token = next_token(&val, cfile);
 675         if (token != SEMI) {
 676                 parse_warn("expecting semicolon.");
 677                 skip_to_semi(cfile);
 678         }
 679 }
 680
 681 struct option *
 682 parse_option_decl(FILE *cfile, struct option_data *options)
 683 {
 684         char            *val;
 685         int              token;
 686         u_int8_t         buf[4];
 687         u_int8_t         hunkbuf[1024];
 688         unsigned         hunkix = 0;
 689         char            *vendor;
 690         char            *fmt;
 691         struct universe *universe;
 692         struct option   *option;
 693         struct iaddr     ip_addr;
 694         u_int8_t        *dp;
 695         unsigned         len;
 696         int              nul_term = 0;
 697
 698         token = next_token(&val, cfile);
 699         if (!is_identifier(token)) {
 700                 parse_warn("expecting identifier after option keyword.");
 701                 if (token != SEMI)
 702                         skip_to_semi(cfile);
 703                 return (NULL);
 704         }
 705         if ((vendor = strdup(val)) == NULL)
 706                 error("no memory for vendor information.");
 707
 708         token = peek_token(&val, cfile);
 709         if (token == DOT) {
 710                 /* Go ahead and take the DOT token... */
 711                 token = next_token(&val, cfile);
 712
 713                 /* The next token should be an identifier... */
 714                 token = next_token(&val, cfile);
 715                 if (!is_identifier(token)) {
 716                         parse_warn("expecting identifier after '.'");
 717                         if (token != SEMI)
 718                                 skip_to_semi(cfile);
 719                         free(vendor);
 720                         return (NULL);
 721                 }
 722
 723                 /* Look up the option name hash table for the specified
 724                    vendor. */
 725                 universe = ((struct universe *)hash_lookup(&universe_hash,
 726                     (unsigned char *)vendor, 0));
 727                 /* If it's not there, we can't parse the rest of the
 728                    declaration. */
 729                 if (!universe) {
 730                         parse_warn("no vendor named %s.", vendor);
 731                         skip_to_semi(cfile);
 732                         free(vendor);
 733                         return (NULL);
 734                 }
 735         } else {
 736                 /* Use the default hash table, which contains all the
 737                    standard dhcp option names. */
 738                 val = vendor;
 739                 universe = &dhcp_universe;
 740         }
 741
 742         /* Look up the actual option info... */
 743         option = (struct option *)hash_lookup(universe->hash,
 744             (unsigned char *)val, 0);
 745
 746         /* If we didn't get an option structure, it's an undefined option. */
 747         if (!option) {
 748                 if (val == vendor)
 749                         parse_warn("no option named %s", val);
 750                 else
 751                         parse_warn("no option named %s for vendor %s",
 752                                     val, vendor);
 753                 skip_to_semi(cfile);
 754                 free(vendor);
 755                 return (NULL);
 756         }
 757
 758         /* Free the initial identifier token. */
 759         free(vendor);
 760
 761         /* Parse the option data... */
 762         do {
 763                 for (fmt = option->format; *fmt; fmt++) {
 764                         if (*fmt == 'A')
 765                                 break;
 766                         switch (*fmt) {
 767                         case 'X':
 768                                 len = parse_X(cfile, &hunkbuf[hunkix],
 769                                     sizeof(hunkbuf) - hunkix);
 770                                 hunkix += len;
 771                                 break;
 772                         case 't': /* Text string... */
 773                                 token = next_token(&val, cfile);
 774                                 if (token != STRING) {
 775                                         parse_warn("expecting string.");
 776                                         skip_to_semi(cfile);
 777                                         return (NULL);
 778                                 }
 779                                 len = strlen(val);
 780                                 if (hunkix + len + 1 > sizeof(hunkbuf)) {
 781                                         parse_warn("option data buffer %s",
 782                                             "overflow");
 783                                         skip_to_semi(cfile);
 784                                         return (NULL);
 785                                 }
 786                                 memcpy(&hunkbuf[hunkix], val, len + 1);
 787                                 nul_term = 1;
 788                                 hunkix += len;
 789                                 break;
 790                         case 'I': /* IP address. */
 791                                 if (!parse_ip_addr(cfile, &ip_addr))
 792                                         return (NULL);
 793                                 len = ip_addr.len;
 794                                 dp = ip_addr.iabuf;
 795 alloc:
 796                                 if (hunkix + len > sizeof(hunkbuf)) {
 797                                         parse_warn("option data buffer "
 798                                             "overflow");
 799                                         skip_to_semi(cfile);
 800                                         return (NULL);
 801                                 }
 802                                 memcpy(&hunkbuf[hunkix], dp, len);
 803                                 hunkix += len;
 804                                 break;
 805                         case 'L':       /* Unsigned 32-bit integer... */
 806                         case 'l':       /* Signed 32-bit integer... */
 807                                 token = next_token(&val, cfile);
 808                                 if (token != NUMBER) {
 809 need_number:
 810                                         parse_warn("expecting number.");
 811                                         if (token != SEMI)
 812                                                 skip_to_semi(cfile);
 813                                         return (NULL);
 814                                 }
 815                                 convert_num(buf, val, 0, 32);
 816                                 len = 4;
 817                                 dp = buf;
 818                                 goto alloc;
 819                         case 's':       /* Signed 16-bit integer. */
 820                         case 'S':       /* Unsigned 16-bit integer. */
 821                                 token = next_token(&val, cfile);
 822                                 if (token != NUMBER)
 823                                         goto need_number;
 824                                 convert_num(buf, val, 0, 16);
 825                                 len = 2;
 826                                 dp = buf;
 827                                 goto alloc;
 828                         case 'b':       /* Signed 8-bit integer. */
 829                         case 'B':       /* Unsigned 8-bit integer. */
 830                                 token = next_token(&val, cfile);
 831                                 if (token != NUMBER)
 832                                         goto need_number;
 833                                 convert_num(buf, val, 0, 8);
 834                                 len = 1;
 835                                 dp = buf;
 836                                 goto alloc;
 837                         case 'f': /* Boolean flag. */
 838                                 token = next_token(&val, cfile);
 839                                 if (!is_identifier(token)) {
 840                                         parse_warn("expecting identifier.");
 841 bad_flag:
 842                                         if (token != SEMI)
 843                                                 skip_to_semi(cfile);
 844                                         return (NULL);
 845                                 }
 846                                 if (!strcasecmp(val, "true") ||
 847                                     !strcasecmp(val, "on"))
 848                                         buf[0] = 1;
 849                                 else if (!strcasecmp(val, "false") ||
 850                                     !strcasecmp(val, "off"))
 851                                         buf[0] = 0;
 852                                 else {
 853                                         parse_warn("expecting boolean.");
 854                                         goto bad_flag;
 855                                 }
 856                                 len = 1;
 857                                 dp = buf;
 858                                 goto alloc;
 859                         default:
 860                                 warning("Bad format %c in parse_option_param.",
 861                                     *fmt);
 862                                 skip_to_semi(cfile);
 863                                 return (NULL);
 864                         }
 865                 }
 866                 token = next_token(&val, cfile);
 867         } while (*fmt == 'A' && token == COMMA);
 868
 869         if (token != SEMI) {
 870                 parse_warn("semicolon expected.");
 871                 skip_to_semi(cfile);
 872                 return (NULL);
 873         }
 874
 875         options[option->code].data = malloc(hunkix + nul_term);
 876         if (!options[option->code].data)
 877                 error("out of memory allocating option data.");
 878         memcpy(options[option->code].data, hunkbuf, hunkix + nul_term);
 879         options[option->code].len = hunkix;
 880         return (option);
 881 }
 882
 883 void
 884 parse_string_list(FILE *cfile, struct string_list **lp, int multiple)
 885 {
 886         int                      token;
 887         char                    *val;
 888         size_t                   valsize;
 889         struct string_list      *cur, *tmp;
 890
 891         /* Find the last medium in the media list. */
 892         if (*lp)
 893                 for (cur = *lp; cur->next; cur = cur->next)
 894                         ;       /* nothing */
 895         else
 896                 cur = NULL;
 897
 898         do {
 899                 token = next_token(&val, cfile);
 900                 if (token != STRING) {
 901                         parse_warn("Expecting media options.");
 902                         skip_to_semi(cfile);
 903                         return;
 904                 }
 905
 906                 valsize = strlen(val) + 1;
 907                 tmp = new_string_list(valsize);
 908                 if (tmp == NULL)
 909                         error("no memory for string list entry.");
 910                 memcpy(tmp->string, val, valsize);
 911                 tmp->next = NULL;
 912
 913                 /* Store this medium at the end of the media list. */
 914                 if (cur)
 915                         cur->next = tmp;
 916                 else
 917                         *lp = tmp;
 918                 cur = tmp;
 919
 920                 token = next_token(&val, cfile);
 921         } while (multiple && token == COMMA);
 922
 923         if (token != SEMI) {
 924                 parse_warn("expecting semicolon.");
 925                 skip_to_semi(cfile);
 926         }
 927 }
 928
 929 void
 930 parse_reject_statement(FILE *cfile, struct client_config *config)
 931 {
 932         int                      token;
 933         char                    *val;
 934         struct iaddr             addr;
 935         struct iaddrlist        *list;
 936
 937         do {
 938                 if (!parse_ip_addr(cfile, &addr)) {
 939                         parse_warn("expecting IP address.");
 940                         skip_to_semi(cfile);
 941                         return;
 942                 }
 943
 944                 list = malloc(sizeof(struct iaddrlist));
 945                 if (!list)
 946                         error("no memory for reject list!");
 947
 948                 list->addr = addr;
 949                 list->next = config->reject_list;
 950                 config->reject_list = list;
 951
 952                 token = next_token(&val, cfile);
 953         } while (token == COMMA);
 954
 955         if (token != SEMI) {
 956                 parse_warn("expecting semicolon.");
 957                 skip_to_semi(cfile);
 958         }
 959 }