dist/dhcp/common/conflex.c

   1 /* conflex.c
   2
   3    Lexical scanner for dhcpd config file... */
   4
   5 /*
   6  * Copyright (c) 2004-2005 by Internet Systems Consortium, Inc. ("ISC")
   7  * Copyright (c) 1995-2003 by Internet Software Consortium
   8  *
   9  * Permission to use, copy, modify, and distribute this software for any
  10  * purpose with or without fee is hereby granted, provided that the above
  11  * copyright notice and this permission notice appear in all copies.
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  14  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  15  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  16  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  17  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  18  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  19  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  20  *
  21  *   Internet Systems Consortium, Inc.
  22  *   950 Charter Street
  23  *   Redwood City, CA 94063
  24  *   <info@isc.org>
  25  *   http://www.isc.org/
  26  *
  27  * This software has been written for Internet Systems Consortium
  28  * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
  29  * To learn more about Internet Systems Consortium, see
  30  * ``http://www.isc.org/''.  To learn more about Vixie Enterprises,
  31  * see ``http://www.vix.com''.   To learn more about Nominum, Inc., see
  32  * ``http://www.nominum.com''.
  33  */
  34
  35 #ifndef lint
  36 static char copyright[] =
  37 "$Id: conflex.c,v 1.5 2005/08/11 17:13:21 drochner Exp $ Copyright (c) 2004-2005 Internet Systems Consortium.  All rights reserved.\n";
  38 #endif /* not lint */
  39
  40 #include "dhcpd.h"
  41 #include <ctype.h>
  42
  43 static int get_char PROTO ((struct parse *));
  44 static enum dhcp_token get_token PROTO ((struct parse *));
  45 static void skip_to_eol PROTO ((struct parse *));
  46 static enum dhcp_token read_string PROTO ((struct parse *));
  47 static enum dhcp_token read_number PROTO ((int, struct parse *));
  48 static enum dhcp_token read_num_or_name PROTO ((int, struct parse *));
  49 static enum dhcp_token intern PROTO ((char *, enum dhcp_token));
  50
  51 isc_result_t new_parse (cfile, file, inbuf, buflen, name, eolp)
  52         struct parse **cfile;
  53         int file;
  54         char *inbuf;
  55         unsigned buflen;
  56         const char *name;
  57         int eolp;
  58 {
  59         struct parse *tmp;
  60
  61         tmp = dmalloc (sizeof (struct parse), MDL);
  62         if (!tmp)
  63                 return ISC_R_NOMEMORY;
  64         memset (tmp, 0, sizeof *tmp);
  65
  66         tmp -> token = 0;
  67         tmp -> tlname = name;
  68         tmp -> lpos = tmp -> line = 1;
  69         tmp -> cur_line = tmp -> line1;
  70         tmp -> prev_line = tmp -> line2;
  71         tmp -> token_line = tmp -> cur_line;
  72         tmp -> cur_line [0] = tmp -> prev_line [0] = 0;
  73         tmp -> warnings_occurred = 0;
  74         tmp -> file = file;
  75         tmp -> eol_token = eolp;
  76
  77         tmp -> bufix = 0;
  78         tmp -> buflen = buflen;
  79         if (inbuf) {
  80                 tmp -> bufsiz = 0;
  81                 tmp -> inbuf = inbuf;
  82         } else {
  83                 tmp -> inbuf = dmalloc (8192, MDL);
  84                 if (!tmp -> inbuf) {
  85                         dfree (tmp, MDL);
  86                         return ISC_R_NOMEMORY;
  87                 }
  88                 tmp -> bufsiz = 8192;
  89         }
  90
  91         *cfile = tmp;
  92         return ISC_R_SUCCESS;
  93 }
  94
  95 isc_result_t end_parse (cfile)
  96         struct parse **cfile;
  97 {
  98         if ((*cfile) -> bufsiz)
  99                 dfree ((*cfile) -> inbuf, MDL);
 100         dfree (*cfile, MDL);
 101         *cfile = (struct parse *)0;
 102         return ISC_R_SUCCESS;
 103 }
 104
 105 static int get_char (cfile)
 106         struct parse *cfile;
 107 {
 108         /* My kingdom for WITH... */
 109         int c;
 110
 111         if (cfile -> bufix == cfile -> buflen) {
 112                 if (cfile -> file != -1) {
 113                         cfile -> buflen =
 114                                 read (cfile -> file,
 115                                       cfile -> inbuf, cfile -> bufsiz);
 116                         if (cfile -> buflen == 0) {
 117                                 c = EOF;
 118                                 cfile -> bufix = 0;
 119                         } else if (cfile -> buflen < 0) {
 120                                 c = EOF;
 121                                 cfile -> bufix = cfile -> buflen = 0;
 122                         } else {
 123                                 c = cfile -> inbuf [0];
 124                                 cfile -> bufix = 1;
 125                         }
 126                 } else
 127                         c = EOF;
 128         } else {
 129                 c = cfile -> inbuf [cfile -> bufix];
 130                 cfile -> bufix++;
 131         }
 132
 133         if (!cfile -> ugflag) {
 134                 if (c == EOL) {
 135                         if (cfile -> cur_line == cfile -> line1) {
 136                                 cfile -> cur_line = cfile -> line2;
 137                                 cfile -> prev_line = cfile -> line1;
 138                         } else {
 139                                 cfile -> cur_line = cfile -> line1;
 140                                 cfile -> prev_line = cfile -> line2;
 141                         }
 142                         cfile -> line++;
 143                         cfile -> lpos = 1;
 144                         cfile -> cur_line [0] = 0;
 145                 } else if (c != EOF) {
 146                         if (cfile -> lpos <= 80) {
 147                                 cfile -> cur_line [cfile -> lpos - 1] = c;
 148                                 cfile -> cur_line [cfile -> lpos] = 0;
 149                         }
 150                         cfile -> lpos++;
 151                 }
 152         } else
 153                 cfile -> ugflag = 0;
 154         return c;
 155 }
 156
 157 static enum dhcp_token get_token (cfile)
 158         struct parse *cfile;
 159 {
 160         int c;
 161         enum dhcp_token ttok;
 162         static char tb [2];
 163         int l, p, u;
 164
 165         do {
 166                 l = cfile -> line;
 167                 p = cfile -> lpos;
 168                 u = cfile -> ugflag;
 169
 170                 c = get_char (cfile);
 171 #ifdef OLD_LEXER
 172                 if (c == '\n' && p == 1 && !u
 173                     && cfile -> comment_index < sizeof cfile -> comments)
 174                         cfile -> comments [cfile -> comment_index++] = '\n';
 175 #endif
 176
 177                 if (!(c == '\n' && cfile -> eol_token)
 178                     && isascii (c) && isspace (c))
 179                         continue;
 180                 if (c == '#') {
 181 #ifdef OLD_LEXER
 182                         if (cfile -> comment_index < sizeof cfile -> comments)
 183                             cfile -> comments [cfile -> comment_index++] = '#';
 184 #endif
 185                         skip_to_eol (cfile);
 186                         continue;
 187                 }
 188                 if (c == '"') {
 189                         cfile -> lexline = l;
 190                         cfile -> lexchar = p;
 191                         ttok = read_string (cfile);
 192                         break;
 193                 }
 194                 if ((isascii (c) && isdigit (c)) || c == '-') {
 195                         cfile -> lexline = l;
 196                         cfile -> lexchar = p;
 197                         ttok = read_number (c, cfile);
 198                         break;
 199                 } else if (isascii (c) && isalpha (c)) {
 200                         cfile -> lexline = l;
 201                         cfile -> lexchar = p;
 202                         ttok = read_num_or_name (c, cfile);
 203                         break;
 204                 } else if (c == EOF) {
 205                         ttok = END_OF_FILE;
 206                         cfile -> tlen = 0;
 207                         break;
 208                 } else {
 209                         cfile -> lexline = l;
 210                         cfile -> lexchar = p;
 211                         tb [0] = c;
 212                         tb [1] = 0;
 213                         cfile -> tval = tb;
 214                         cfile -> tlen = 1;
 215                         ttok = c;
 216                         break;
 217                 }
 218         } while (1);
 219         return ttok;
 220 }
 221
 222 enum dhcp_token next_token (rval, rlen, cfile)
 223         const char **rval;
 224         unsigned *rlen;
 225         struct parse *cfile;
 226 {
 227         int rv;
 228
 229         if (cfile -> token) {
 230                 if (cfile -> lexline != cfile -> tline)
 231                         cfile -> token_line = cfile -> cur_line;
 232                 cfile -> lexchar = cfile -> tlpos;
 233                 cfile -> lexline = cfile -> tline;
 234                 rv = cfile -> token;
 235                 cfile -> token = 0;
 236         } else {
 237                 rv = get_token (cfile);
 238                 cfile -> token_line = cfile -> cur_line;
 239         }
 240         if (rval)
 241                 *rval = cfile -> tval;
 242         if (rlen)
 243                 *rlen = cfile -> tlen;
 244 #ifdef DEBUG_TOKENS
 245         fprintf (stderr, "%s:%d ", cfile -> tval, rv);
 246 #endif
 247         return rv;
 248 }
 249
 250 enum dhcp_token peek_token (rval, rlen, cfile)
 251         const char **rval;
 252         unsigned int *rlen;
 253         struct parse *cfile;
 254 {
 255         int x;
 256
 257         if (!cfile -> token) {
 258                 cfile -> tlpos = cfile -> lexchar;
 259                 cfile -> tline = cfile -> lexline;
 260                 cfile -> token = get_token (cfile);
 261                 if (cfile -> lexline != cfile -> tline)
 262                         cfile -> token_line = cfile -> prev_line;
 263
 264                 x = cfile -> lexchar;
 265                 cfile -> lexchar = cfile -> tlpos;
 266                 cfile -> tlpos = x;
 267
 268                 x = cfile -> lexline;
 269                 cfile -> lexline = cfile -> tline;
 270                 cfile -> tline = x;
 271         }
 272         if (rval)
 273                 *rval = cfile -> tval;
 274         if (rlen)
 275                 *rlen = cfile -> tlen;
 276 #ifdef DEBUG_TOKENS
 277         fprintf (stderr, "(%s:%d) ", cfile -> tval, cfile -> token);
 278 #endif
 279         return cfile -> token;
 280 }
 281
 282 static void skip_to_eol (cfile)
 283         struct parse *cfile;
 284 {
 285         int c;
 286         do {
 287                 c = get_char (cfile);
 288                 if (c == EOF)
 289                         return;
 290 #ifdef OLD_LEXER
 291                 if (cfile -> comment_index < sizeof (cfile -> comments))
 292                         comments [cfile -> comment_index++] = c;
 293 #endif
 294                 if (c == EOL) {
 295                         return;
 296                 }
 297         } while (1);
 298 }
 299
 300 static enum dhcp_token read_string (cfile)
 301         struct parse *cfile;
 302 {
 303         int i;
 304         int bs = 0;
 305         int c;
 306         int value = 0;
 307         int hex = 0;
 308
 309         value = 0;      /* XXXGCC -Wuninitialized */
 310         hex = 0;        /* XXXGCC -Wuninitialized */
 311
 312         for (i = 0; i < sizeof cfile -> tokbuf; i++) {
 313               again:
 314                 c = get_char (cfile);
 315                 if (c == EOF) {
 316                         parse_warn (cfile, "eof in string constant");
 317                         break;
 318                 }
 319                 if (bs == 1) {
 320                         switch (c) {
 321                               case 't':
 322                                 cfile -> tokbuf [i] = '\t';
 323                                 break;
 324                               case 'r':
 325                                 cfile -> tokbuf [i] = '\r';
 326                                 break;
 327                               case 'n':
 328                                 cfile -> tokbuf [i] = '\n';
 329                                 break;
 330                               case 'b':
 331                                 cfile -> tokbuf [i] = '\b';
 332                                 break;
 333                               case '0':
 334                               case '1':
 335                               case '2':
 336                               case '3':
 337                                 hex = 0;
 338                                 value = c - '0';
 339                                 ++bs;
 340                                 goto again;
 341                               case 'x':
 342                                 hex = 1;
 343                                 value = 0;
 344                                 ++bs;
 345                                 goto again;
 346                               default:
 347                                 cfile -> tokbuf [i] = c;
 348                                 bs = 0;
 349                                 break;
 350                         }
 351                         bs = 0;
 352                 } else if (bs > 1) {
 353                         if (hex) {
 354                                 if (c >= '0' && c <= '9') {
 355                                         value = value * 16 + (c - '0');
 356                                 } else if (c >= 'a' && c <= 'f') {
 357                                         value = value * 16 + (c - 'a' + 10);
 358                                 } else if (c >= 'A' && c <= 'F') {
 359                                         value = value * 16 + (c - 'A' + 10);
 360                                 } else {
 361                                         parse_warn (cfile,
 362                                                     "invalid hex digit: %x",
 363                                                     c);
 364                                         bs = 0;
 365                                         continue;
 366                                 }
 367                                 if (++bs == 4) {
 368                                         cfile -> tokbuf [i] = value;
 369                                         bs = 0;
 370                                 } else
 371                                         goto again;
 372                         } else {
 373                                 if (c >= '0' && c <= '9') {
 374                                         value = value * 8 + (c - '0');
 375                                 } else {
 376                                     if (value != 0) {
 377                                         parse_warn (cfile,
 378                                                     "invalid octal digit %x",
 379                                                     c);
 380                                         continue;
 381                                     } else
 382                                         cfile -> tokbuf [i] = 0;
 383                                     bs = 0;
 384                                 }
 385                                 if (++bs == 4) {
 386                                         cfile -> tokbuf [i] = value;
 387                                         bs = 0;
 388                                 } else
 389                                         goto again;
 390                         }
 391                 } else if (c == '\\') {
 392                         bs = 1;
 393                         goto again;
 394                 } else if (c == '"')
 395                         break;
 396                 else
 397                         cfile -> tokbuf [i] = c;
 398         }
 399         /* Normally, I'd feel guilty about this, but we're talking about
 400            strings that'll fit in a DHCP packet here... */
 401         if (i == sizeof cfile -> tokbuf) {
 402                 parse_warn (cfile,
 403                             "string constant larger than internal buffer");
 404                 --i;
 405         }
 406         cfile -> tokbuf [i] = 0;
 407         cfile -> tlen = i;
 408         cfile -> tval = cfile -> tokbuf;
 409         return STRING;
 410 }
 411
 412 static enum dhcp_token read_number (c, cfile)
 413         int c;
 414         struct parse *cfile;
 415 {
 416 #ifdef OLD_LEXER
 417         int seenx = 0;
 418 #endif
 419         int i = 0;
 420         int token = NUMBER;
 421
 422         cfile -> tokbuf [i++] = c;
 423         for (; i < sizeof cfile -> tokbuf; i++) {
 424                 c = get_char (cfile);
 425
 426 #ifndef OLD_LEXER
 427                 /* Promote NUMBER -> NUMBER_OR_NAME -> NAME, never demote.
 428                  * Except in the case of '0x' syntax hex, which gets called
 429                  * a NAME at '0x', and returned to NUMBER_OR_NAME once it's
 430                  * verified to be at least 0xf or less.
 431                  */
 432                 switch(isascii(c) ? token : BREAK) {
 433                     case NUMBER:
 434                         if(isdigit(c))
 435                                 break;
 436                         /* FALLTHROUGH */
 437                     case NUMBER_OR_NAME:
 438                         if(isxdigit(c)) {
 439                                 token = NUMBER_OR_NAME;
 440                                 break;
 441                         }
 442                         /* FALLTHROUGH */
 443                     case NAME:
 444                         if((i == 2) && isxdigit(c) &&
 445                                 (cfile->tokbuf[0] == '0') &&
 446                                 ((cfile->tokbuf[1] == 'x') ||
 447                                  (cfile->tokbuf[1] == 'X'))) {
 448                                 token = NUMBER_OR_NAME;
 449                                 break;
 450                         } else if(((c == '-') || (c == '_') || isalnum(c))) {
 451                                 token = NAME;
 452                                 break;
 453                         }
 454                         /* FALLTHROUGH */
 455                     case BREAK:
 456                         /* At this point c is either EOF or part of the next
 457                          * token.  If not EOF, rewind the file one byte so
 458                          * the next token is read from there.
 459                          */
 460                         if(c != EOF) {
 461                                 cfile->bufix--;
 462                                 cfile->ugflag = 1;
 463                         }
 464                         goto end_read;
 465
 466                     default:
 467                         log_fatal("read_number():%s:%d: impossible case", MDL);
 468                 }
 469 #else /* OLD_LEXER */
 470                 if (!seenx && (c == 'x') {
 471                         seenx = 1;
 472                 } else if (!isascii (c) || !isxdigit (c)) {
 473                         if (c != EOF) {
 474                                 cfile -> bufix--;
 475                                 cfile -> ugflag = 1;
 476                         }
 477                         break;
 478                 }
 479 #endif /* OLD_LEXER */
 480
 481                 cfile -> tokbuf [i] = c;
 482         }
 483
 484         if (i == sizeof cfile -> tokbuf) {
 485                 parse_warn (cfile,
 486                             "numeric token larger than internal buffer");
 487                 --i;
 488         }
 489
 490   end_read:
 491         cfile -> tokbuf [i] = 0;
 492         cfile -> tlen = i;
 493         cfile -> tval = cfile -> tokbuf;
 494
 495         return token;
 496 }
 497
 498 static enum dhcp_token read_num_or_name (c, cfile)
 499         int c;
 500         struct parse *cfile;
 501 {
 502         int i = 0;
 503         enum dhcp_token rv = NUMBER_OR_NAME;
 504         cfile -> tokbuf [i++] = c;
 505         for (; i < sizeof cfile -> tokbuf; i++) {
 506                 c = get_char (cfile);
 507                 if (!isascii (c) ||
 508                     (c != '-' && c != '_' && !isalnum (c))) {
 509                         if (c != EOF) {
 510                                 cfile -> bufix--;
 511                                 cfile -> ugflag = 1;
 512                         }
 513                         break;
 514                 }
 515                 if (!isxdigit (c))
 516                         rv = NAME;
 517                 cfile -> tokbuf [i] = c;
 518         }
 519         if (i == sizeof cfile -> tokbuf) {
 520                 parse_warn (cfile, "token larger than internal buffer");
 521                 --i;
 522         }
 523         cfile -> tokbuf [i] = 0;
 524         cfile -> tlen = i;
 525         cfile -> tval = cfile -> tokbuf;
 526         return intern (cfile -> tval, rv);
 527 }
 528
 529 static enum dhcp_token intern (atom, dfv)
 530         char *atom;
 531         enum dhcp_token dfv;
 532 {
 533         if (!isascii (atom [0]))
 534                 return dfv;
 535
 536         switch (tolower ((unsigned char)atom [0])) {
 537               case '-':
 538                 if (atom [1] == 0)
 539                         return MINUS;
 540                 break;
 541
 542               case 'a':
 543                 if (!strncasecmp (atom + 1, "uth", 3)) {
 544                         if (!strncasecmp (atom + 3, "uthenticat", 10)) {
 545                                 if (!strcasecmp (atom + 13, "ed"))
 546                                         return AUTHENTICATED;
 547                                 if (!strcasecmp (atom + 13, "ion"))
 548                                         return AUTHENTICATION;
 549                                 break;
 550                         }
 551                         if (!strcasecmp (atom + 1, "uthoritative"))
 552                                 return AUTHORITATIVE;
 553                         break;
 554                 }
 555                 if (!strcasecmp (atom + 1, "nd"))
 556                         return AND;
 557                 if (!strcasecmp (atom + 1, "ppend"))
 558                         return APPEND;
 559                 if (!strcasecmp (atom + 1, "llow"))
 560                         return ALLOW;
 561                 if (!strcasecmp (atom + 1, "lias"))
 562                         return ALIAS;
 563                 if (!strcasecmp (atom + 1, "lgorithm"))
 564                         return ALGORITHM;
 565                 if (!strcasecmp (atom + 1, "bandoned"))
 566                         return TOKEN_ABANDONED;
 567                 if (!strcasecmp (atom + 1, "dd"))
 568                         return TOKEN_ADD;
 569                 if (!strcasecmp (atom + 1, "ll"))
 570                         return ALL;
 571                 if (!strcasecmp (atom + 1, "t"))
 572                         return AT;
 573                 if (!strcasecmp (atom + 1, "rray"))
 574                         return ARRAY;
 575                 if (!strcasecmp (atom + 1, "ddress"))
 576                         return ADDRESS;
 577                 if (!strcasecmp (atom + 1, "ctive"))
 578                         return TOKEN_ACTIVE;
 579                 break;
 580               case 'b':
 581                 if (!strcasecmp (atom + 1, "ackup"))
 582                         return TOKEN_BACKUP;
 583                 if (!strcasecmp (atom + 1, "ootp"))
 584                         return TOKEN_BOOTP;
 585                 if (!strcasecmp (atom + 1, "inding"))
 586                         return BINDING;
 587                 if (!strcasecmp (atom + 1, "inary-to-ascii"))
 588                         return BINARY_TO_ASCII;
 589                 if (!strcasecmp (atom + 1, "ackoff-cutoff"))
 590                         return BACKOFF_CUTOFF;
 591                 if (!strcasecmp (atom + 1, "ooting"))
 592                         return BOOTING;
 593                 if (!strcasecmp (atom + 1, "oot-unknown-clients"))
 594                         return BOOT_UNKNOWN_CLIENTS;
 595                 if (!strcasecmp (atom + 1, "reak"))
 596                         return BREAK;
 597                 if (!strcasecmp (atom + 1, "illing"))
 598                         return BILLING;
 599                 if (!strcasecmp (atom + 1, "oolean"))
 600                         return BOOLEAN;
 601                 if (!strcasecmp (atom + 1, "alance"))
 602                         return BALANCE;
 603                 if (!strcasecmp (atom + 1, "ound"))
 604                         return BOUND;
 605                 break;
 606               case 'c':
 607                 if (!strcasecmp (atom + 1, "ase"))
 608                         return CASE;
 609                 if (!strcasecmp (atom + 1, "ommit"))
 610                         return COMMIT;
 611                 if (!strcasecmp (atom + 1, "ode"))
 612                         return CODE;
 613                 if (!strcasecmp (atom + 1, "onfig-option"))
 614                         return CONFIG_OPTION;
 615                 if (!strcasecmp (atom + 1, "heck"))
 616                         return CHECK;
 617                 if (!strcasecmp (atom + 1, "lass"))
 618                         return CLASS;
 619                 if (!strcasecmp (atom + 1, "lose"))
 620                         return TOKEN_CLOSE;
 621                 if (!strcasecmp (atom + 1, "reate"))
 622                         return TOKEN_CREATE;
 623                 if (!strcasecmp (atom + 1, "iaddr"))
 624                         return CIADDR;
 625                 if (!strncasecmp (atom + 1, "lient", 5)) {
 626                         if (!strcasecmp (atom + 6, "-identifier"))
 627                                 return CLIENT_IDENTIFIER;
 628                         if (!strcasecmp (atom + 6, "-hostname"))
 629                                 return CLIENT_HOSTNAME;
 630                         if (!strcasecmp (atom + 6, "-state"))
 631                                 return CLIENT_STATE;
 632                         if (!strcasecmp (atom + 6, "-updates"))
 633                                 return CLIENT_UPDATES;
 634                         if (!strcasecmp (atom + 6, "s"))
 635                                 return CLIENTS;
 636                 }
 637                 if (!strcasecmp (atom + 1, "oncat"))
 638                         return CONCAT;
 639                 if (!strcasecmp (atom + 1, "onnect"))
 640                         return CONNECT;
 641                 if (!strcasecmp (atom + 1, "ommunications-interrupted"))
 642                         return COMMUNICATIONS_INTERRUPTED;
 643                 if (!strcasecmp (atom + 1, "ltt"))
 644                         return CLTT;
 645                 break;
 646               case 'd':
 647                 if (!strcasecmp (atom + 1, "ns-update"))
 648                         return DNS_UPDATE;
 649                 if (!strcasecmp (atom + 1, "ns-delete"))
 650                         return DNS_DELETE;
 651                 if (!strcasecmp (atom + 1, "omain"))
 652                         return DOMAIN;
 653                 if (!strcasecmp (atom + 1, "omain-name"))
 654                         return DOMAIN_NAME;
 655                 if (!strcasecmp (atom + 1, "o-forward-update"))
 656                         return DO_FORWARD_UPDATE;
 657                 if (!strcasecmp (atom + 1, "ebug"))
 658                         return TOKEN_DEBUG;
 659                 if (!strcasecmp (atom + 1, "eny"))
 660                         return DENY;
 661                 if (!strcasecmp (atom + 1, "eleted"))
 662                         return TOKEN_DELETED;
 663                 if (!strcasecmp (atom + 1, "elete"))
 664                         return TOKEN_DELETE;
 665                 if (!strncasecmp (atom + 1, "efault", 6)) {
 666                         if (!atom [7])
 667                                 return DEFAULT;
 668                         if (!strcasecmp (atom + 7, "-lease-time"))
 669                                 return DEFAULT_LEASE_TIME;
 670                         break;
 671                 }
 672                 if (!strncasecmp (atom + 1, "ynamic", 6)) {
 673                         if (!atom [7])
 674                                 return DYNAMIC;
 675                         if (!strncasecmp (atom + 7, "-bootp", 6)) {
 676                                 if (!atom [13])
 677                                         return DYNAMIC_BOOTP;
 678                                 if (!strcasecmp (atom + 13, "-lease-cutoff"))
 679                                         return DYNAMIC_BOOTP_LEASE_CUTOFF;
 680                                 if (!strcasecmp (atom + 13, "-lease-length"))
 681                                         return DYNAMIC_BOOTP_LEASE_LENGTH;
 682                                 break;
 683                         }
 684                 }
 685                 if (!strcasecmp (atom + 1, "uplicates"))
 686                         return DUPLICATES;
 687                 if (!strcasecmp (atom + 1, "eclines"))
 688                         return DECLINES;
 689                 if (!strncasecmp (atom + 1, "efine", 5)) {
 690                         if (!strcasecmp (atom + 6, "d"))
 691                                 return DEFINED;
 692                         if (!atom [6])
 693                                 return DEFINE;
 694                 }
 695                 break;
 696               case 'e':
 697                 if (tolower ((unsigned char)atom [1]) == 'x') {
 698                         if (!strcasecmp (atom + 2, "tract-int"))
 699                                 return EXTRACT_INT;
 700                         if (!strcasecmp (atom + 2, "ists"))
 701                                 return EXISTS;
 702                         if (!strcasecmp (atom + 2, "piry"))
 703                                 return EXPIRY;
 704                         if (!strcasecmp (atom + 2, "pire"))
 705                                 return EXPIRE;
 706                         if (!strcasecmp (atom + 2, "pired"))
 707                                 return TOKEN_EXPIRED;
 708                 }
 709                 if (!strcasecmp (atom + 1, "ncode-int"))
 710                         return ENCODE_INT;
 711                 if (!strcasecmp (atom + 1, "thernet"))
 712                         return ETHERNET;
 713                 if (!strcasecmp (atom + 1, "nds"))
 714                         return ENDS;
 715                 if (!strncasecmp (atom + 1, "ls", 2)) {
 716                         if (!strcasecmp (atom + 3, "e"))
 717                                 return ELSE;
 718                         if (!strcasecmp (atom + 3, "if"))
 719                                 return ELSIF;
 720                         break;
 721                 }
 722                 if (!strcasecmp (atom + 1, "rror"))
 723                         return ERROR;
 724                 if (!strcasecmp (atom + 1, "val"))
 725                         return EVAL;
 726                 if (!strcasecmp (atom + 1, "ncapsulate"))
 727                         return ENCAPSULATE;
 728                 break;
 729               case 'f':
 730                 if (!strcasecmp (atom + 1, "atal"))
 731                         return FATAL;
 732                 if (!strcasecmp (atom + 1, "ilename"))
 733                         return FILENAME;
 734                 if (!strcasecmp (atom + 1, "ixed-address"))
 735                         return FIXED_ADDR;
 736                 if (!strcasecmp (atom + 1, "ddi"))
 737                         return FDDI;
 738                 if (!strcasecmp (atom + 1, "ormerr"))
 739                         return NS_FORMERR;
 740                 if (!strcasecmp (atom + 1, "unction"))
 741                         return FUNCTION;
 742                 if (!strcasecmp (atom + 1, "ailover"))
 743                         return FAILOVER;
 744                 if (!strcasecmp (atom + 1, "ree"))
 745                         return TOKEN_FREE;
 746                 break;
 747               case 'g':
 748                 if (!strcasecmp (atom + 1, "iaddr"))
 749                         return GIADDR;
 750                 if (!strcasecmp (atom + 1, "roup"))
 751                         return GROUP;
 752                 if (!strcasecmp (atom + 1, "et-lease-hostnames"))
 753                         return GET_LEASE_HOSTNAMES;
 754                 break;
 755               case 'h':
 756                 if (!strcasecmp (atom + 1, "ba"))
 757                         return HBA;
 758                 if (!strcasecmp (atom + 1, "ost"))
 759                         return HOST;
 760                 if (!strcasecmp (atom + 1, "ost-decl-name"))
 761                         return HOST_DECL_NAME;
 762                 if (!strcasecmp (atom + 1, "ardware"))
 763                         return HARDWARE;
 764                 if (!strcasecmp (atom + 1, "ostname"))
 765                         return HOSTNAME;
 766                 if (!strcasecmp (atom + 1, "elp"))
 767                         return TOKEN_HELP;
 768                 break;
 769               case 'i':
 770                 if (!strcasecmp (atom + 1, "nclude"))
 771                         return INCLUDE;
 772                 if (!strcasecmp (atom + 1, "nteger"))
 773                         return INTEGER;
 774                 if (!strcasecmp (atom + 1, "nfinite"))
 775                         return INFINITE;
 776                 if (!strcasecmp (atom + 1, "nfo"))
 777                         return INFO;
 778                 if (!strcasecmp (atom + 1, "p-address"))
 779                         return IP_ADDRESS;
 780                 if (!strcasecmp (atom + 1, "nitial-interval"))
 781                         return INITIAL_INTERVAL;
 782                 if (!strcasecmp (atom + 1, "nterface"))
 783                         return INTERFACE;
 784                 if (!strcasecmp (atom + 1, "dentifier"))
 785                         return IDENTIFIER;
 786                 if (!strcasecmp (atom + 1, "f"))
 787                         return IF;
 788                 if (!strcasecmp (atom + 1, "s"))
 789                         return IS;
 790                 if (!strcasecmp (atom + 1, "gnore"))
 791                         return IGNORE;
 792                 break;
 793               case 'k':
 794                 if (!strncasecmp (atom + 1, "nown", 4)) {
 795                         if (!strcasecmp (atom + 5, "-clients"))
 796                                 return KNOWN_CLIENTS;
 797                         if (!atom[5])
 798                                 return KNOWN;
 799                         break;
 800                 }
 801                 if (!strcasecmp (atom + 1, "ey"))
 802                         return KEY;
 803                 break;
 804               case 'l':
 805                 if (!strcasecmp (atom + 1, "ease"))
 806                         return LEASE;
 807                 if (!strcasecmp (atom + 1, "eased-address"))
 808                         return LEASED_ADDRESS;
 809                 if (!strcasecmp (atom + 1, "ease-time"))
 810                         return LEASE_TIME;
 811                 if (!strcasecmp (atom + 1, "imit"))
 812                         return LIMIT;
 813                 if (!strcasecmp (atom + 1, "et"))
 814                         return LET;
 815                 if (!strcasecmp (atom + 1, "oad"))
 816                         return LOAD;
 817                 if (!strcasecmp (atom + 1, "og"))
 818                         return LOG;
 819                 break;
 820               case 'm':
 821                 if (!strncasecmp (atom + 1, "ax", 2)) {
 822                         if (!atom [3])
 823                                 return TOKEN_MAX;
 824                         if (!strcasecmp (atom + 3, "-lease-time"))
 825                                 return MAX_LEASE_TIME;
 826                         if (!strcasecmp (atom + 3, "-transmit-idle"))
 827                                 return MAX_TRANSMIT_IDLE;
 828                         if (!strcasecmp (atom + 3, "-response-delay"))
 829                                 return MAX_RESPONSE_DELAY;
 830                         if (!strcasecmp (atom + 3, "-unacked-updates"))
 831                                 return MAX_UNACKED_UPDATES;
 832                 }
 833                 if (!strncasecmp (atom + 1, "in-", 3)) {
 834                         if (!strcasecmp (atom + 4, "lease-time"))
 835                                 return MIN_LEASE_TIME;
 836                         if (!strcasecmp (atom + 4, "secs"))
 837                                 return MIN_SECS;
 838                         break;
 839                 }
 840                 if (!strncasecmp (atom + 1, "edi", 3)) {
 841                         if (!strcasecmp (atom + 4, "a"))
 842                                 return MEDIA;
 843                         if (!strcasecmp (atom + 4, "um"))
 844                                 return MEDIUM;
 845                         break;
 846                 }
 847                 if (!strcasecmp (atom + 1, "atch"))
 848                         return MATCH;
 849                 if (!strcasecmp (atom + 1, "embers"))
 850                         return MEMBERS;
 851                 if (!strcasecmp (atom + 1, "y"))
 852                         return MY;
 853                 if (!strcasecmp (atom + 1, "clt"))
 854                         return MCLT;
 855                 break;
 856               case 'n':
 857                 if (!strcasecmp (atom + 1, "ormal"))
 858                         return NORMAL;
 859                 if (!strcasecmp (atom + 1, "ameserver"))
 860                         return NAMESERVER;
 861                 if (!strcasecmp (atom + 1, "etmask"))
 862                         return NETMASK;
 863                 if (!strcasecmp (atom + 1, "ever"))
 864                         return NEVER;
 865                 if (!strcasecmp (atom + 1, "ext-server"))
 866                         return NEXT_SERVER;
 867                 if (!strcasecmp (atom + 1, "ot"))
 868                         return TOKEN_NOT;
 869                 if (!strcasecmp (atom + 1, "o"))
 870                         return NO;
 871                 if (!strcasecmp (atom + 1, "s-update"))
 872                         return NS_UPDATE;
 873                 if (!strcasecmp (atom + 1, "oerror"))
 874                         return NS_NOERROR;
 875                 if (!strcasecmp (atom + 1, "otauth"))
 876                         return NS_NOTAUTH;
 877                 if (!strcasecmp (atom + 1, "otimp"))
 878                         return NS_NOTIMP;
 879                 if (!strcasecmp (atom + 1, "otzone"))
 880                         return NS_NOTZONE;
 881                 if (!strcasecmp (atom + 1, "xdomain"))
 882                         return NS_NXDOMAIN;
 883                 if (!strcasecmp (atom + 1, "xrrset"))
 884                         return NS_NXRRSET;
 885                 if (!strcasecmp (atom + 1, "ull"))
 886                         return TOKEN_NULL;
 887                 if (!strcasecmp (atom + 1, "ext"))
 888                         return TOKEN_NEXT;
 889                 if (!strcasecmp (atom + 1, "ew"))
 890                         return TOKEN_NEW;
 891                 break;
 892               case 'o':
 893                 if (!strcasecmp (atom + 1, "mapi"))
 894                         return OMAPI;
 895                 if (!strcasecmp (atom + 1, "r"))
 896                         return OR;
 897                 if (!strcasecmp (atom + 1, "n"))
 898                         return ON;
 899                 if (!strcasecmp (atom + 1, "pen"))
 900                         return TOKEN_OPEN;
 901                 if (!strcasecmp (atom + 1, "ption"))
 902                         return OPTION;
 903                 if (!strcasecmp (atom + 1, "ne-lease-per-client"))
 904                         return ONE_LEASE_PER_CLIENT;
 905                 if (!strcasecmp (atom + 1, "f"))
 906                         return OF;
 907                 if (!strcasecmp (atom + 1, "wner"))
 908                         return OWNER;
 909                 break;
 910               case 'p':
 911                 if (!strcasecmp (atom + 1, "repend"))
 912                         return PREPEND;
 913                 if (!strcasecmp (atom + 1, "acket"))
 914                         return PACKET;
 915                 if (!strcasecmp (atom + 1, "ool"))
 916                         return POOL;
 917                 if (!strcasecmp (atom + 1, "seudo"))
 918                         return PSEUDO;
 919                 if (!strcasecmp (atom + 1, "eer"))
 920                         return PEER;
 921                 if (!strcasecmp (atom + 1, "rimary"))
 922                         return PRIMARY;
 923                 if (!strncasecmp (atom + 1, "artner", 6)) {
 924                         if (!atom [7])
 925                                 return PARTNER;
 926                         if (!strcasecmp (atom + 7, "-down"))
 927                                 return PARTNER_DOWN;
 928                 }
 929                 if (!strcasecmp (atom + 1, "ort"))
 930                         return PORT;
 931                 if (!strcasecmp (atom + 1, "otential-conflict"))
 932                         return POTENTIAL_CONFLICT;
 933                 if (!strcasecmp (atom + 1, "ick-first-value") ||
 934                     !strcasecmp (atom + 1, "ick"))
 935                         return PICK;
 936                 if (!strcasecmp (atom + 1, "aused"))
 937                         return PAUSED;
 938                 break;
 939               case 'r':
 940                 if (!strcasecmp (atom + 1, "esolution-interrupted"))
 941                         return RESOLUTION_INTERRUPTED;
 942                 if (!strcasecmp (atom + 1, "ange"))
 943                         return RANGE;
 944                 if (!strcasecmp (atom + 1, "ecover"))
 945                         return RECOVER;
 946                 if (!strcasecmp (atom + 1, "ecover-done"))
 947                         return RECOVER_DONE;
 948                 if (!strcasecmp (atom + 1, "ecover-wait"))
 949                         return RECOVER_WAIT;
 950                 if (!strcasecmp (atom + 1, "econtact-interval"))
 951                         return RECONTACT_INTERVAL;
 952                 if (!strcasecmp (atom + 1, "equest"))
 953                         return REQUEST;
 954                 if (!strcasecmp (atom + 1, "equire"))
 955                         return REQUIRE;
 956                 if (!strcasecmp (atom + 1, "equire"))
 957                         return REQUIRE;
 958                 if (!strcasecmp (atom + 1, "etry"))
 959                         return RETRY;
 960                 if (!strcasecmp (atom + 1, "eturn"))
 961                         return RETURN;
 962                 if (!strcasecmp (atom + 1, "enew"))
 963                         return RENEW;
 964                 if (!strcasecmp (atom + 1, "ebind"))
 965                         return REBIND;
 966                 if (!strcasecmp (atom + 1, "eboot"))
 967                         return REBOOT;
 968                 if (!strcasecmp (atom + 1, "eject"))
 969                         return REJECT;
 970                 if (!strcasecmp (atom + 1, "everse"))
 971                         return REVERSE;
 972                 if (!strcasecmp (atom + 1, "elease"))
 973                         return RELEASE;
 974                 if (!strcasecmp (atom + 1, "efused"))
 975                         return NS_REFUSED;
 976                 if (!strcasecmp (atom + 1, "eleased"))
 977                         return TOKEN_RELEASED;
 978                 if (!strcasecmp (atom + 1, "eset"))
 979                         return TOKEN_RESET;
 980                 if (!strcasecmp (atom + 1, "eserved"))
 981                         return TOKEN_RESERVED;
 982                 if (!strcasecmp (atom + 1, "emove"))
 983                         return REMOVE;
 984                 if (!strcasecmp (atom + 1, "efresh"))
 985                         return REFRESH;
 986                 break;
 987               case 's':
 988                 if (!strcasecmp (atom + 1, "tate"))
 989                         return STATE;
 990                 if (!strcasecmp (atom + 1, "ecret"))
 991                         return SECRET;
 992                 if (!strcasecmp (atom + 1, "ervfail"))
 993                         return NS_SERVFAIL;
 994                 if (!strcasecmp (atom + 1, "witch"))
 995                         return SWITCH;
 996                 if (!strcasecmp (atom + 1, "igned"))
 997                         return SIGNED;
 998                 if (!strcasecmp (atom + 1, "tring"))
 999                         return STRING_TOKEN;
1000                 if (!strcasecmp (atom + 1, "uffix"))
1001                         return SUFFIX;
1002                 if (!strcasecmp (atom + 1, "earch"))
1003                         return SEARCH;
1004                 if (!strcasecmp (atom + 1, "tarts"))
1005                         return STARTS;
1006                 if (!strcasecmp (atom + 1, "iaddr"))
1007                         return SIADDR;
1008                 if (!strcasecmp (atom + 1, "hared-network"))
1009                         return SHARED_NETWORK;
1010                 if (!strcasecmp (atom + 1, "econdary"))
1011                         return SECONDARY;
1012                 if (!strcasecmp (atom + 1, "erver-name"))
1013                         return SERVER_NAME;
1014                 if (!strcasecmp (atom + 1, "erver-identifier"))
1015                         return SERVER_IDENTIFIER;
1016                 if (!strcasecmp (atom + 1, "erver"))
1017                         return SERVER;
1018                 if (!strcasecmp (atom + 1, "elect-timeout"))
1019                         return SELECT_TIMEOUT;
1020                 if (!strcasecmp (atom + 1, "elect"))
1021                         return SELECT;
1022                 if (!strcasecmp (atom + 1, "end"))
1023                         return SEND;
1024                 if (!strcasecmp (atom + 1, "cript"))
1025                         return SCRIPT;
1026                 if (!strcasecmp (atom + 1, "upersede"))
1027                         return SUPERSEDE;
1028                 if (!strncasecmp (atom + 1, "ub", 2)) {
1029                         if (!strcasecmp (atom + 3, "string"))
1030                                 return SUBSTRING;
1031                         if (!strcasecmp (atom + 3, "net"))
1032                                 return SUBNET;
1033                         if (!strcasecmp (atom + 3, "class"))
1034                                 return SUBCLASS;
1035                         break;
1036                 }
1037                 if (!strcasecmp (atom + 1, "pawn"))
1038                         return SPAWN;
1039                 if (!strcasecmp (atom + 1, "pace"))
1040                         return SPACE;
1041                 if (!strcasecmp (atom + 1, "tatic"))
1042                         return STATIC;
1043                 if (!strcasecmp (atom + 1, "plit"))
1044                         return SPLIT;
1045                 if (!strcasecmp (atom + 1, "et"))
1046                         return TOKEN_SET;
1047                 if (!strcasecmp (atom + 1, "econds"))
1048                         return SECONDS;
1049                 if (!strcasecmp (atom + 1, "hutdown"))
1050                         return SHUTDOWN;
1051                 if (!strcasecmp (atom + 1, "tartup"))
1052                         return STARTUP;
1053                 break;
1054               case 't':
1055                 if (!strcasecmp (atom + 1, "imestamp"))
1056                         return TIMESTAMP;
1057                 if (!strcasecmp (atom + 1, "imeout"))
1058                         return TIMEOUT;
1059                 if (!strcasecmp (atom + 1, "oken-ring"))
1060                         return TOKEN_RING;
1061                 if (!strcasecmp (atom + 1, "ext"))
1062                         return TEXT;
1063                 if (!strcasecmp (atom + 1, "stp"))
1064                         return TSTP;
1065                 if (!strcasecmp (atom + 1, "sfp"))
1066                         return TSFP;
1067                 if (!strcasecmp (atom + 1, "ransmission"))
1068                         return TRANSMISSION;
1069                 break;
1070               case 'u':
1071                 if (!strcasecmp (atom + 1, "nset"))
1072                         return UNSET;
1073                 if (!strcasecmp (atom + 1, "nsigned"))
1074                         return UNSIGNED;
1075                 if (!strcasecmp (atom + 1, "id"))
1076                         return UID;
1077                 if (!strncasecmp (atom + 1, "se", 2)) {
1078                         if (!strcasecmp (atom + 3, "r-class"))
1079                                 return USER_CLASS;
1080                         if (!strcasecmp (atom + 3, "-host-decl-names"))
1081                                 return USE_HOST_DECL_NAMES;
1082                         if (!strcasecmp (atom + 3,
1083                                          "-lease-addr-for-default-route"))
1084                                 return USE_LEASE_ADDR_FOR_DEFAULT_ROUTE;
1085                         break;
1086                 }
1087                 if (!strncasecmp (atom + 1, "nknown", 6)) {
1088                         if (!strcasecmp (atom + 7, "-clients"))
1089                                 return UNKNOWN_CLIENTS;
1090                         if (!strcasecmp (atom + 7, "-state"))
1091                                 return UNKNOWN_STATE;
1092                         if (!atom [7])
1093                                 return UNKNOWN;
1094                         break;
1095                 }
1096                 if (!strcasecmp (atom + 1, "nauthenticated"))
1097                         return AUTHENTICATED;
1098                 if (!strcasecmp (atom + 1, "pdated-dns-rr"))
1099                         return UPDATED_DNS_RR;
1100                 if (!strcasecmp (atom + 1, "pdate"))
1101                         return UPDATE;
1102                 break;
1103               case 'v':
1104                 if (!strcasecmp (atom + 1, "endor-class"))
1105                         return VENDOR_CLASS;
1106                 if (!strcasecmp (atom + 1, "endor"))
1107                         return VENDOR;
1108                 break;
1109               case 'w':
1110                 if (!strcasecmp (atom + 1, "ith"))
1111                         return WITH;
1112                 break;
1113               case 'y':
1114                 if (!strcasecmp (atom + 1, "iaddr"))
1115                         return YIADDR;
1116                 if (!strcasecmp (atom + 1, "xdomain"))
1117                         return NS_YXDOMAIN;
1118                 if (!strcasecmp (atom + 1, "xrrset"))
1119                         return NS_YXRRSET;
1120                 break;
1121               case 'z':
1122                 if (!strcasecmp (atom + 1, "one"))
1123                         return ZONE;
1124                 break;
1125         }
1126         return dfv;
1127 }