common/conflex.c

   1 /* conflex.c
   2
   3    Lexical scanner for dhcpd config file... */
   4
   5 /*
   6  * Copyright (c) 1995-2001 Internet Software Consortium.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of The Internet Software Consortium nor the names
  19  *    of its contributors may be used to endorse or promote products derived
  20  *    from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
  23  * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  24  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  25  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  26  * DISCLAIMED.  IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
  27  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  29  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  30  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  31  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  32  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  33  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  * This software has been written for the Internet Software Consortium
  37  * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
  38  * To learn more about the Internet Software Consortium, see
  39  * ``http://www.isc.org/''.  To learn more about Vixie Enterprises,
  40  * see ``http://www.vix.com''.   To learn more about Nominum, Inc., see
  41  * ``http://www.nominum.com''.
  42  */
  43
  44 #ifndef lint
  45 static char copyright[] =
  46 "$Id: conflex.c,v 1.94 2001/06/27 00:29:42 mellon Exp $ Copyright (c) 1995-2001 The Internet Software Consortium.  All rights reserved.\n";
  47 #endif /* not lint */
  48
  49 #include "dhcpd.h"
  50 #include <ctype.h>
  51
  52 static int get_char PROTO ((struct parse *));
  53 static enum dhcp_token get_token PROTO ((struct parse *));
  54 static void skip_to_eol PROTO ((struct parse *));
  55 static enum dhcp_token read_string PROTO ((struct parse *));
  56 static enum dhcp_token read_number PROTO ((int, struct parse *));
  57 static enum dhcp_token read_num_or_name PROTO ((int, struct parse *));
  58 static enum dhcp_token intern PROTO ((char *, enum dhcp_token));
  59
  60 isc_result_t new_parse (cfile, file, inbuf, buflen, name, eolp)
  61         struct parse **cfile;
  62         int file;
  63         char *inbuf;
  64         unsigned buflen;
  65         const char *name;
  66         int eolp;
  67 {
  68         struct parse *tmp;
  69
  70         tmp = dmalloc (sizeof (struct parse), MDL);
  71         if (!tmp)
  72                 return ISC_R_NOMEMORY;
  73         memset (tmp, 0, sizeof *tmp);
  74
  75         tmp -> token = 0;
  76         tmp -> tlname = name;
  77         tmp -> lpos = tmp -> line = 1;
  78         tmp -> cur_line = tmp -> line1;
  79         tmp -> prev_line = tmp -> line2;
  80         tmp -> token_line = tmp -> cur_line;
  81         tmp -> cur_line [0] = tmp -> prev_line [0] = 0;
  82         tmp -> warnings_occurred = 0;
  83         tmp -> file = file;
  84         tmp -> eol_token = eolp;
  85
  86         tmp -> bufix = 0;
  87         tmp -> buflen = buflen;
  88         if (inbuf) {
  89                 tmp -> bufsiz = 0;
  90                 tmp -> inbuf = inbuf;
  91         } else {
  92                 tmp -> inbuf = dmalloc (8192, MDL);
  93                 if (!tmp -> inbuf) {
  94                         dfree (tmp, MDL);
  95                         return ISC_R_NOMEMORY;
  96                 }
  97                 tmp -> bufsiz = 8192;
  98         }
  99
 100         *cfile = tmp;
 101         return ISC_R_SUCCESS;
 102 }
 103
 104 isc_result_t end_parse (cfile)
 105         struct parse **cfile;
 106 {
 107         if ((*cfile) -> bufsiz)
 108                 dfree ((*cfile) -> inbuf, MDL);
 109         dfree (*cfile, MDL);
 110         *cfile = (struct parse *)0;
 111         return ISC_R_SUCCESS;
 112 }
 113
 114 static int get_char (cfile)
 115         struct parse *cfile;
 116 {
 117         /* My kingdom for WITH... */
 118         int c;
 119
 120         if (cfile -> bufix == cfile -> buflen) {
 121                 if (cfile -> file != -1) {
 122                         cfile -> buflen =
 123                                 read (cfile -> file,
 124                                       cfile -> inbuf, cfile -> bufsiz);
 125                         if (cfile -> buflen == 0) {
 126                                 c = EOF;
 127                                 cfile -> bufix = 0;
 128                         } else if (cfile -> buflen < 0) {
 129                                 c = EOF;
 130                                 cfile -> bufix = cfile -> buflen = 0;
 131                         } else {
 132                                 c = cfile -> inbuf [0];
 133                                 cfile -> bufix = 1;
 134                         }
 135                 } else
 136                         c = EOF;
 137         } else {
 138                 c = cfile -> inbuf [cfile -> bufix];
 139                 cfile -> bufix++;
 140         }
 141
 142         if (!cfile -> ugflag) {
 143                 if (c == EOL) {
 144                         if (cfile -> cur_line == cfile -> line1) {
 145                                 cfile -> cur_line = cfile -> line2;
 146                                 cfile -> prev_line = cfile -> line1;
 147                         } else {
 148                                 cfile -> cur_line = cfile -> line1;
 149                                 cfile -> prev_line = cfile -> line2;
 150                         }
 151                         cfile -> line++;
 152                         cfile -> lpos = 1;
 153                         cfile -> cur_line [0] = 0;
 154                 } else if (c != EOF) {
 155                         if (cfile -> lpos <= 80) {
 156                                 cfile -> cur_line [cfile -> lpos - 1] = c;
 157                                 cfile -> cur_line [cfile -> lpos] = 0;
 158                         }
 159                         cfile -> lpos++;
 160                 }
 161         } else
 162                 cfile -> ugflag = 0;
 163         return c;
 164 }
 165
 166 static enum dhcp_token get_token (cfile)
 167         struct parse *cfile;
 168 {
 169         int c;
 170         enum dhcp_token ttok;
 171         static char tb [2];
 172         int l, p, u;
 173
 174         do {
 175                 l = cfile -> line;
 176                 p = cfile -> lpos;
 177                 u = cfile -> ugflag;
 178
 179                 c = get_char (cfile);
 180 #ifdef OLD_LEXER
 181                 if (c == '\n' && p == 1 && !u
 182                     && cfile -> comment_index < sizeof cfile -> comments)
 183                         cfile -> comments [cfile -> comment_index++] = '\n';
 184 #endif
 185
 186                 if (!(c == '\n' && cfile -> eol_token)
 187                     && isascii (c) && isspace (c))
 188                         continue;
 189                 if (c == '#') {
 190 #ifdef OLD_LEXER
 191                         if (cfile -> comment_index < sizeof cfile -> comments)
 192                             cfile -> comments [cfile -> comment_index++] = '#';
 193 #endif
 194                         skip_to_eol (cfile);
 195                         continue;
 196                 }
 197                 if (c == '"') {
 198                         cfile -> lexline = l;
 199                         cfile -> lexchar = p;
 200                         ttok = read_string (cfile);
 201                         break;
 202                 }
 203                 if ((isascii (c) && isdigit (c)) || c == '-') {
 204                         cfile -> lexline = l;
 205                         cfile -> lexchar = p;
 206                         ttok = read_number (c, cfile);
 207                         break;
 208                 } else if (isascii (c) && isalpha (c)) {
 209                         cfile -> lexline = l;
 210                         cfile -> lexchar = p;
 211                         ttok = read_num_or_name (c, cfile);
 212                         break;
 213                 } else if (c == EOF) {
 214                         ttok = END_OF_FILE;
 215                         cfile -> tlen = 0;
 216                         break;
 217                 } else {
 218                         cfile -> lexline = l;
 219                         cfile -> lexchar = p;
 220                         tb [0] = c;
 221                         tb [1] = 0;
 222                         cfile -> tval = tb;
 223                         cfile -> tlen = 1;
 224                         ttok = c;
 225                         break;
 226                 }
 227         } while (1);
 228         return ttok;
 229 }
 230
 231 enum dhcp_token next_token (rval, rlen, cfile)
 232         const char **rval;
 233         unsigned *rlen;
 234         struct parse *cfile;
 235 {
 236         int rv;
 237
 238         if (cfile -> token) {
 239                 if (cfile -> lexline != cfile -> tline)
 240                         cfile -> token_line = cfile -> cur_line;
 241                 cfile -> lexchar = cfile -> tlpos;
 242                 cfile -> lexline = cfile -> tline;
 243                 rv = cfile -> token;
 244                 cfile -> token = 0;
 245         } else {
 246                 rv = get_token (cfile);
 247                 cfile -> token_line = cfile -> cur_line;
 248         }
 249         if (rval)
 250                 *rval = cfile -> tval;
 251         if (rlen)
 252                 *rlen = cfile -> tlen;
 253 #ifdef DEBUG_TOKENS
 254         fprintf (stderr, "%s:%d ", cfile -> tval, rv);
 255 #endif
 256         return rv;
 257 }
 258
 259 enum dhcp_token peek_token (rval, rlen, cfile)
 260         const char **rval;
 261         unsigned int *rlen;
 262         struct parse *cfile;
 263 {
 264         int x;
 265
 266         if (!cfile -> token) {
 267                 cfile -> tlpos = cfile -> lexchar;
 268                 cfile -> tline = cfile -> lexline;
 269                 cfile -> token = get_token (cfile);
 270                 if (cfile -> lexline != cfile -> tline)
 271                         cfile -> token_line = cfile -> prev_line;
 272
 273                 x = cfile -> lexchar;
 274                 cfile -> lexchar = cfile -> tlpos;
 275                 cfile -> tlpos = x;
 276
 277                 x = cfile -> lexline;
 278                 cfile -> lexline = cfile -> tline;
 279                 cfile -> tline = x;
 280         }
 281         if (rval)
 282                 *rval = cfile -> tval;
 283         if (rlen)
 284                 *rlen = cfile -> tlen;
 285 #ifdef DEBUG_TOKENS
 286         fprintf (stderr, "(%s:%d) ", cfile -> tval, cfile -> token);
 287 #endif
 288         return cfile -> token;
 289 }
 290
 291 static void skip_to_eol (cfile)
 292         struct parse *cfile;
 293 {
 294         int c;
 295         do {
 296                 c = get_char (cfile);
 297                 if (c == EOF)
 298                         return;
 299 #ifdef OLD_LEXER
 300                 if (cfile -> comment_index < sizeof (cfile -> comments))
 301                         comments [cfile -> comment_index++] = c;
 302 #endif
 303                 if (c == EOL) {
 304                         return;
 305                 }
 306         } while (1);
 307 }
 308
 309 static enum dhcp_token read_string (cfile)
 310         struct parse *cfile;
 311 {
 312         int i;
 313         int bs = 0;
 314         int c;
 315         int value;
 316         int hex;
 317
 318         for (i = 0; i < sizeof cfile -> tokbuf; i++) {
 319               again:
 320                 c = get_char (cfile);
 321                 if (c == EOF) {
 322                         parse_warn (cfile, "eof in string constant");
 323                         break;
 324                 }
 325                 if (bs == 1) {
 326                         switch (c) {
 327                               case 't':
 328                                 cfile -> tokbuf [i] = '\t';
 329                                 break;
 330                               case 'r':
 331                                 cfile -> tokbuf [i] = '\r';
 332                                 break;
 333                               case 'n':
 334                                 cfile -> tokbuf [i] = '\n';
 335                                 break;
 336                               case 'b':
 337                                 cfile -> tokbuf [i] = '\b';
 338                                 break;
 339                               case '0':
 340                               case '1':
 341                               case '2':
 342                               case '3':
 343                                 hex = 0;
 344                                 value = c - '0';
 345                                 ++bs;
 346                                 goto again;
 347                               case 'x':
 348                                 hex = 1;
 349                                 value = 0;
 350                                 ++bs;
 351                                 goto again;
 352                               default:
 353                                 cfile -> tokbuf [i] = c;
 354                                 bs = 0;
 355                                 break;
 356                         }
 357                         bs = 0;
 358                 } else if (bs > 1) {
 359                         if (hex) {
 360                                 if (c >= '0' && c <= '9') {
 361                                         value = value * 16 + (c - '0');
 362                                 } else if (c >= 'a' && c <= 'f') {
 363                                         value = value * 16 + (c - 'a' + 10);
 364                                 } else if (c >= 'A' && c <= 'F') {
 365                                         value = value * 16 + (c - 'A' + 10);
 366                                 } else {
 367                                         parse_warn (cfile,
 368                                                     "invalid hex digit: %x",
 369                                                     c);
 370                                         bs = 0;
 371                                         continue;
 372                                 }
 373                                 if (++bs == 4) {
 374                                         cfile -> tokbuf [i] = value;
 375                                         bs = 0;
 376                                 } else
 377                                         goto again;
 378                         } else {
 379                                 if (c >= '0' && c <= '9') {
 380                                         value = value * 8 + (c - '0');
 381                                 } else {
 382                                     if (value != 0) {
 383                                         parse_warn (cfile,
 384                                                     "invalid octal digit %x",
 385                                                     c);
 386                                         continue;
 387                                     } else
 388                                         cfile -> tokbuf [i] = 0;
 389                                     bs = 0;
 390                                 }
 391                                 if (++bs == 4) {
 392                                         cfile -> tokbuf [i] = value;
 393                                         bs = 0;
 394                                 } else
 395                                         goto again;
 396                         }
 397                 } else if (c == '\\') {
 398                         bs = 1;
 399                         goto again;
 400                 } else if (c == '"')
 401                         break;
 402                 else
 403                         cfile -> tokbuf [i] = c;
 404         }
 405         /* Normally, I'd feel guilty about this, but we're talking about
 406            strings that'll fit in a DHCP packet here... */
 407         if (i == sizeof cfile -> tokbuf) {
 408                 parse_warn (cfile,
 409                             "string constant larger than internal buffer");
 410                 --i;
 411         }
 412         cfile -> tokbuf [i] = 0;
 413         cfile -> tlen = i;
 414         cfile -> tval = cfile -> tokbuf;
 415         return STRING;
 416 }
 417
 418 static enum dhcp_token read_number (c, cfile)
 419         int c;
 420         struct parse *cfile;
 421 {
 422         int seenx = 0;
 423         int i = 0;
 424         int token = NUMBER;
 425
 426         cfile -> tokbuf [i++] = c;
 427         for (; i < sizeof cfile -> tokbuf; i++) {
 428                 c = get_char (cfile);
 429                 if (!seenx && c == 'x') {
 430                         seenx = 1;
 431 #ifndef OLD_LEXER
 432                 } else if (isascii (c) && !isxdigit (c) &&
 433                            (c == '-' || c == '_' || isalpha (c))) {
 434                         token = NAME;
 435                 } else if (isascii (c) && !isdigit (c) && isxdigit (c)) {
 436                         token = NUMBER_OR_NAME;
 437 #endif
 438                 } else if (!isascii (c) || !isxdigit (c)) {
 439                         cfile -> bufix--;
 440                         cfile -> ugflag = 1;
 441                         break;
 442                 }
 443                 cfile -> tokbuf [i] = c;
 444         }
 445         if (i == sizeof cfile -> tokbuf) {
 446                 parse_warn (cfile,
 447                             "numeric token larger than internal buffer");
 448                 --i;
 449         }
 450         cfile -> tokbuf [i] = 0;
 451         cfile -> tlen = i;
 452         cfile -> tval = cfile -> tokbuf;
 453         return token;
 454 }
 455
 456 static enum dhcp_token read_num_or_name (c, cfile)
 457         int c;
 458         struct parse *cfile;
 459 {
 460         int i = 0;
 461         enum dhcp_token rv = NUMBER_OR_NAME;
 462         cfile -> tokbuf [i++] = c;
 463         for (; i < sizeof cfile -> tokbuf; i++) {
 464                 c = get_char (cfile);
 465                 if (!isascii (c) ||
 466                     (c != '-' && c != '_' && !isalnum (c))) {
 467                         cfile -> bufix--;
 468                         cfile -> ugflag = 1;
 469                         break;
 470                 }
 471                 if (!isxdigit (c))
 472                         rv = NAME;
 473                 cfile -> tokbuf [i] = c;
 474         }
 475         if (i == sizeof cfile -> tokbuf) {
 476                 parse_warn (cfile, "token larger than internal buffer");
 477                 --i;
 478         }
 479         cfile -> tokbuf [i] = 0;
 480         cfile -> tlen = i;
 481         cfile -> tval = cfile -> tokbuf;
 482         return intern (cfile -> tval, rv);
 483 }
 484
 485 static enum dhcp_token intern (atom, dfv)
 486         char *atom;
 487         enum dhcp_token dfv;
 488 {
 489         if (!isascii (atom [0]))
 490                 return dfv;
 491
 492         switch (tolower (atom [0])) {
 493               case '-':
 494                 if (atom [1] == 0)
 495                         return MINUS;
 496                 break;
 497
 498               case 'a':
 499                 if (!strncasecmp (atom + 1, "uth", 3)) {
 500                         if (!strncasecmp (atom + 3, "uthenticat", 10)) {
 501                                 if (!strcasecmp (atom + 13, "ed"))
 502                                         return AUTHENTICATED;
 503                                 if (!strcasecmp (atom + 13, "ion"))
 504                                         return AUTHENTICATION;
 505                                 break;
 506                         }
 507                         if (!strcasecmp (atom + 1, "uthoritative"))
 508                                 return AUTHORITATIVE;
 509                         break;
 510                 }
 511                 if (!strcasecmp (atom + 1, "nd"))
 512                         return AND;
 513                 if (!strcasecmp (atom + 1, "ppend"))
 514                         return APPEND;
 515                 if (!strcasecmp (atom + 1, "llow"))
 516                         return ALLOW;
 517                 if (!strcasecmp (atom + 1, "lias"))
 518                         return ALIAS;
 519                 if (!strcasecmp (atom + 1, "lgorithm"))
 520                         return ALGORITHM;
 521                 if (!strcasecmp (atom + 1, "bandoned"))
 522                         return TOKEN_ABANDONED;
 523                 if (!strcasecmp (atom + 1, "dd"))
 524                         return TOKEN_ADD;
 525                 if (!strcasecmp (atom + 1, "ll"))
 526                         return ALL;
 527                 if (!strcasecmp (atom + 1, "t"))
 528                         return AT;
 529                 if (!strcasecmp (atom + 1, "rray"))
 530                         return ARRAY;
 531                 if (!strcasecmp (atom + 1, "ddress"))
 532                         return ADDRESS;
 533                 if (!strcasecmp (atom + 1, "ctive"))
 534                         return TOKEN_ACTIVE;
 535                 break;
 536               case 'b':
 537                 if (!strcasecmp (atom + 1, "ackup"))
 538                         return TOKEN_BACKUP;
 539                 if (!strcasecmp (atom + 1, "ootp"))
 540                         return TOKEN_BOOTP;
 541                 if (!strcasecmp (atom + 1, "inding"))
 542                         return BINDING;
 543                 if (!strcasecmp (atom + 1, "inary-to-ascii"))
 544                         return BINARY_TO_ASCII;
 545                 if (!strcasecmp (atom + 1, "ackoff-cutoff"))
 546                         return BACKOFF_CUTOFF;
 547                 if (!strcasecmp (atom + 1, "ooting"))
 548                         return BOOTING;
 549                 if (!strcasecmp (atom + 1, "oot-unknown-clients"))
 550                         return BOOT_UNKNOWN_CLIENTS;
 551                 if (!strcasecmp (atom + 1, "reak"))
 552                         return BREAK;
 553                 if (!strcasecmp (atom + 1, "illing"))
 554                         return BILLING;
 555                 if (!strcasecmp (atom + 1, "oolean"))
 556                         return BOOLEAN;
 557                 if (!strcasecmp (atom + 1, "alance"))
 558                         return BALANCE;
 559                 if (!strcasecmp (atom + 1, "ound"))
 560                         return BOUND;
 561                 break;
 562               case 'c':
 563                 if (!strcasecmp (atom + 1, "ase"))
 564                         return CASE;
 565                 if (!strcasecmp (atom + 1, "ommit"))
 566                         return COMMIT;
 567                 if (!strcasecmp (atom + 1, "ode"))
 568                         return CODE;
 569                 if (!strcasecmp (atom + 1, "onfig-option"))
 570                         return CONFIG_OPTION;
 571                 if (!strcasecmp (atom + 1, "heck"))
 572                         return CHECK;
 573                 if (!strcasecmp (atom + 1, "lass"))
 574                         return CLASS;
 575                 if (!strcasecmp (atom + 1, "lose"))
 576                         return TOKEN_CLOSE;
 577                 if (!strcasecmp (atom + 1, "reate"))
 578                         return TOKEN_CREATE;
 579                 if (!strcasecmp (atom + 1, "iaddr"))
 580                         return CIADDR;
 581                 if (!strncasecmp (atom + 1, "lient", 5)) {
 582                         if (!strcasecmp (atom + 6, "-identifier"))
 583                                 return CLIENT_IDENTIFIER;
 584                         if (!strcasecmp (atom + 6, "-hostname"))
 585                                 return CLIENT_HOSTNAME;
 586                         if (!strcasecmp (atom + 6, "-state"))
 587                                 return CLIENT_STATE;
 588                         if (!strcasecmp (atom + 6, "-updates"))
 589                                 return CLIENT_UPDATES;
 590                         if (!strcasecmp (atom + 6, "s"))
 591                                 return CLIENTS;
 592                 }
 593                 if (!strcasecmp (atom + 1, "oncat"))
 594                         return CONCAT;
 595                 if (!strcasecmp (atom + 1, "onnect"))
 596                         return CONNECT;
 597                 if (!strcasecmp (atom + 1, "ommunications-interrupted"))
 598                         return COMMUNICATIONS_INTERRUPTED;
 599                 if (!strcasecmp (atom + 1, "ltt"))
 600                         return CLTT;
 601                 break;
 602               case 'd':
 603                 if (!strcasecmp (atom + 1, "ns-update"))
 604                         return DNS_UPDATE;
 605                 if (!strcasecmp (atom + 1, "ns-delete"))
 606                         return DNS_DELETE;
 607                 if (!strcasecmp (atom + 1, "omain"))
 608                         return DOMAIN;
 609                 if (!strcasecmp (atom + 1, "omain-name"))
 610                         return DOMAIN_NAME;
 611                 if (!strcasecmp (atom + 1, "ebug"))
 612                         return TOKEN_DEBUG;
 613                 if (!strcasecmp (atom + 1, "eny"))
 614                         return DENY;
 615                 if (!strcasecmp (atom + 1, "eleted"))
 616                         return TOKEN_DELETED;
 617                 if (!strcasecmp (atom + 1, "elete"))
 618                         return TOKEN_DELETE;
 619                 if (!strncasecmp (atom + 1, "efault", 6)) {
 620                         if (!atom [7])
 621                                 return DEFAULT;
 622                         if (!strcasecmp (atom + 7, "-lease-time"))
 623                                 return DEFAULT_LEASE_TIME;
 624                         break;
 625                 }
 626                 if (!strncasecmp (atom + 1, "ynamic", 6)) {
 627                         if (!atom [7])
 628                                 return DYNAMIC;
 629                         if (!strncasecmp (atom + 7, "-bootp", 6)) {
 630                                 if (!atom [13])
 631                                         return DYNAMIC_BOOTP;
 632                                 if (!strcasecmp (atom + 13, "-lease-cutoff"))
 633                                         return DYNAMIC_BOOTP_LEASE_CUTOFF;
 634                                 if (!strcasecmp (atom + 13, "-lease-length"))
 635                                         return DYNAMIC_BOOTP_LEASE_LENGTH;
 636                                 break;
 637                         }
 638                 }
 639                 if (!strcasecmp (atom + 1, "uplicates"))
 640                         return DUPLICATES;
 641                 if (!strcasecmp (atom + 1, "eclines"))
 642                         return DECLINES;
 643                 if (!strncasecmp (atom + 1, "efine", 5)) {
 644                         if (!strcasecmp (atom + 6, "d"))
 645                                 return DEFINED;
 646                         if (!atom [6])
 647                                 return DEFINE;
 648                 }
 649                 break;
 650               case 'e':
 651                 if (isascii (atom [1]) && tolower (atom [1]) == 'x') {
 652                         if (!strcasecmp (atom + 2, "tract-int"))
 653                                 return EXTRACT_INT;
 654                         if (!strcasecmp (atom + 2, "ists"))
 655                                 return EXISTS;
 656                         if (!strcasecmp (atom + 2, "piry"))
 657                                 return EXPIRY;
 658                         if (!strcasecmp (atom + 2, "pire"))
 659                                 return EXPIRE;
 660                         if (!strcasecmp (atom + 2, "pired"))
 661                                 return TOKEN_EXPIRED;
 662                 }
 663                 if (!strcasecmp (atom + 1, "ncode-int"))
 664                         return ENCODE_INT;
 665                 if (!strcasecmp (atom + 1, "thernet"))
 666                         return ETHERNET;
 667                 if (!strcasecmp (atom + 1, "nds"))
 668                         return ENDS;
 669                 if (!strncasecmp (atom + 1, "ls", 2)) {
 670                         if (!strcasecmp (atom + 3, "e"))
 671                                 return ELSE;
 672                         if (!strcasecmp (atom + 3, "if"))
 673                                 return ELSIF;
 674                         break;
 675                 }
 676                 if (!strcasecmp (atom + 1, "rror"))
 677                         return ERROR;
 678                 if (!strcasecmp (atom + 1, "val"))
 679                         return EVAL;
 680                 if (!strcasecmp (atom + 1, "ncapsulate"))
 681                         return ENCAPSULATE;
 682                 break;
 683               case 'f':
 684                 if (!strcasecmp (atom + 1, "atal"))
 685                         return FATAL;
 686                 if (!strcasecmp (atom + 1, "ilename"))
 687                         return FILENAME;
 688                 if (!strcasecmp (atom + 1, "ixed-address"))
 689                         return FIXED_ADDR;
 690                 if (!strcasecmp (atom + 1, "ddi"))
 691                         return FDDI;
 692                 if (!strcasecmp (atom + 1, "ormerr"))
 693                         return NS_FORMERR;
 694                 if (!strcasecmp (atom + 1, "unction"))
 695                         return FUNCTION;
 696                 if (!strcasecmp (atom + 1, "ailover"))
 697                         return FAILOVER;
 698                 if (!strcasecmp (atom + 1, "ree"))
 699                         return TOKEN_FREE;
 700                 break;
 701               case 'g':
 702                 if (!strcasecmp (atom + 1, "iaddr"))
 703                         return GIADDR;
 704                 if (!strcasecmp (atom + 1, "roup"))
 705                         return GROUP;
 706                 if (!strcasecmp (atom + 1, "et-lease-hostnames"))
 707                         return GET_LEASE_HOSTNAMES;
 708                 break;
 709               case 'h':
 710                 if (!strcasecmp (atom + 1, "ba"))
 711                         return HBA;
 712                 if (!strcasecmp (atom + 1, "ost"))
 713                         return HOST;
 714                 if (!strcasecmp (atom + 1, "ost-decl-name"))
 715                         return HOST_DECL_NAME;
 716                 if (!strcasecmp (atom + 1, "ardware"))
 717                         return HARDWARE;
 718                 if (!strcasecmp (atom + 1, "ostname"))
 719                         return HOSTNAME;
 720                 if (!strcasecmp (atom + 1, "elp"))
 721                         return TOKEN_HELP;
 722                 break;
 723               case 'i':
 724                 if (!strcasecmp (atom + 1, "nclude"))
 725                         return INCLUDE;
 726                 if (!strcasecmp (atom + 1, "nteger"))
 727                         return INTEGER;
 728                 if (!strcasecmp (atom + 1, "nfinite"))
 729                         return INFINITE;
 730                 if (!strcasecmp (atom + 1, "nfo"))
 731                         return INFO;
 732                 if (!strcasecmp (atom + 1, "p-address"))
 733                         return IP_ADDRESS;
 734                 if (!strcasecmp (atom + 1, "nitial-interval"))
 735                         return INITIAL_INTERVAL;
 736                 if (!strcasecmp (atom + 1, "nterface"))
 737                         return INTERFACE;
 738                 if (!strcasecmp (atom + 1, "dentifier"))
 739                         return IDENTIFIER;
 740                 if (!strcasecmp (atom + 1, "f"))
 741                         return IF;
 742                 if (!strcasecmp (atom + 1, "s"))
 743                         return IS;
 744                 if (!strcasecmp (atom + 1, "gnore"))
 745                         return IGNORE;
 746                 break;
 747               case 'k':
 748                 if (!strcasecmp (atom + 1, "nown"))
 749                         return KNOWN;
 750                 if (!strcasecmp (atom + 1, "ey"))
 751                         return KEY;
 752                 break;
 753               case 'l':
 754                 if (!strcasecmp (atom + 1, "ease"))
 755                         return LEASE;
 756                 if (!strcasecmp (atom + 1, "eased-address"))
 757                         return LEASED_ADDRESS;
 758                 if (!strcasecmp (atom + 1, "ease-time"))
 759                         return LEASE_TIME;
 760                 if (!strcasecmp (atom + 1, "imit"))
 761                         return LIMIT;
 762                 if (!strcasecmp (atom + 1, "et"))
 763                         return LET;
 764                 if (!strcasecmp (atom + 1, "oad"))
 765                         return LOAD;
 766                 if (!strcasecmp (atom + 1, "og"))
 767                         return LOG;
 768                 break;
 769               case 'm':
 770                 if (!strncasecmp (atom + 1, "ax", 2)) {
 771                         if (!atom [3])
 772                                 return TOKEN_MAX;
 773                         if (!strcasecmp (atom + 3, "-lease-time"))
 774                                 return MAX_LEASE_TIME;
 775                         if (!strcasecmp (atom + 3, "-transmit-idle"))
 776                                 return MAX_TRANSMIT_IDLE;
 777                         if (!strcasecmp (atom + 3, "-response-delay"))
 778                                 return MAX_RESPONSE_DELAY;
 779                         if (!strcasecmp (atom + 3, "-unacked-updates"))
 780                                 return MAX_UNACKED_UPDATES;
 781                 }
 782                 if (!strncasecmp (atom + 1, "in-", 3)) {
 783                         if (!strcasecmp (atom + 4, "lease-time"))
 784                                 return MIN_LEASE_TIME;
 785                         if (!strcasecmp (atom + 4, "secs"))
 786                                 return MIN_SECS;
 787                         break;
 788                 }
 789                 if (!strncasecmp (atom + 1, "edi", 3)) {
 790                         if (!strcasecmp (atom + 4, "a"))
 791                                 return MEDIA;
 792                         if (!strcasecmp (atom + 4, "um"))
 793                                 return MEDIUM;
 794                         break;
 795                 }
 796                 if (!strcasecmp (atom + 1, "atch"))
 797                         return MATCH;
 798                 if (!strcasecmp (atom + 1, "embers"))
 799                         return MEMBERS;
 800                 if (!strcasecmp (atom + 1, "y"))
 801                         return MY;
 802                 if (!strcasecmp (atom + 1, "clt"))
 803                         return MCLT;
 804                 break;
 805               case 'n':
 806                 if (!strcasecmp (atom + 1, "ormal"))
 807                         return NORMAL;
 808                 if (!strcasecmp (atom + 1, "ameserver"))
 809                         return NAMESERVER;
 810                 if (!strcasecmp (atom + 1, "etmask"))
 811                         return NETMASK;
 812                 if (!strcasecmp (atom + 1, "ever"))
 813                         return NEVER;
 814                 if (!strcasecmp (atom + 1, "ext-server"))
 815                         return NEXT_SERVER;
 816                 if (!strcasecmp (atom + 1, "ot"))
 817                         return TOKEN_NOT;
 818                 if (!strcasecmp (atom + 1, "o"))
 819                         return NO;
 820                 if (!strcasecmp (atom + 1, "s-update"))
 821                         return NS_UPDATE;
 822                 if (!strcasecmp (atom + 1, "oerror"))
 823                         return NS_NOERROR;
 824                 if (!strcasecmp (atom + 1, "otauth"))
 825                         return NS_NOTAUTH;
 826                 if (!strcasecmp (atom + 1, "otimp"))
 827                         return NS_NOTIMP;
 828                 if (!strcasecmp (atom + 1, "otzone"))
 829                         return NS_NOTZONE;
 830                 if (!strcasecmp (atom + 1, "xdomain"))
 831                         return NS_NXDOMAIN;
 832                 if (!strcasecmp (atom + 1, "xrrset"))
 833                         return NS_NXRRSET;
 834                 if (!strcasecmp (atom + 1, "ull"))
 835                         return TOKEN_NULL;
 836                 if (!strcasecmp (atom + 1, "ext"))
 837                         return TOKEN_NEXT;
 838                 if (!strcasecmp (atom + 1, "ew"))
 839                         return TOKEN_NEW;
 840                 break;
 841               case 'o':
 842                 if (!strcasecmp (atom + 1, "mapi"))
 843                         return OMAPI;
 844                 if (!strcasecmp (atom + 1, "r"))
 845                         return OR;
 846                 if (!strcasecmp (atom + 1, "n"))
 847                         return ON;
 848                 if (!strcasecmp (atom + 1, "pen"))
 849                         return TOKEN_OPEN;
 850                 if (!strcasecmp (atom + 1, "ption"))
 851                         return OPTION;
 852                 if (!strcasecmp (atom + 1, "ne-lease-per-client"))
 853                         return ONE_LEASE_PER_CLIENT;
 854                 if (!strcasecmp (atom + 1, "f"))
 855                         return OF;
 856                 if (!strcasecmp (atom + 1, "wner"))
 857                         return OWNER;
 858                 break;
 859               case 'p':
 860                 if (!strcasecmp (atom + 1, "repend"))
 861                         return PREPEND;
 862                 if (!strcasecmp (atom + 1, "acket"))
 863                         return PACKET;
 864                 if (!strcasecmp (atom + 1, "ool"))
 865                         return POOL;
 866                 if (!strcasecmp (atom + 1, "seudo"))
 867                         return PSEUDO;
 868                 if (!strcasecmp (atom + 1, "eer"))
 869                         return PEER;
 870                 if (!strcasecmp (atom + 1, "rimary"))
 871                         return PRIMARY;
 872                 if (!strncasecmp (atom + 1, "artner", 6)) {
 873                         if (!atom [7])
 874                                 return PARTNER;
 875                         if (!strcasecmp (atom + 7, "-down"))
 876                                 return PARTNER_DOWN;
 877                 }
 878                 if (!strcasecmp (atom + 1, "ort"))
 879                         return PORT;
 880                 if (!strcasecmp (atom + 1, "otential-conflict"))
 881                         return POTENTIAL_CONFLICT;
 882                 if (!strcasecmp (atom + 1, "ick-first-value") ||
 883                     !strcasecmp (atom + 1, "ick"))
 884                         return PICK;
 885                 if (!strcasecmp (atom + 1, "aused"))
 886                         return PAUSED;
 887                 break;
 888               case 'r':
 889                 if (!strcasecmp (atom + 1, "esolution-interrupted"))
 890                         return RESOLUTION_INTERRUPTED;
 891                 if (!strcasecmp (atom + 1, "ange"))
 892                         return RANGE;
 893                 if (!strcasecmp (atom + 1, "ecover"))
 894                         return RECOVER;
 895                 if (!strcasecmp (atom + 1, "ecover-done"))
 896                         return RECOVER_DONE;
 897                 if (!strcasecmp (atom + 1, "ecover-wait"))
 898                         return RECOVER_WAIT;
 899                 if (!strcasecmp (atom + 1, "econtact-interval"))
 900                         return RECONTACT_INTERVAL;
 901                 if (!strcasecmp (atom + 1, "equest"))
 902                         return REQUEST;
 903                 if (!strcasecmp (atom + 1, "equire"))
 904                         return REQUIRE;
 905                 if (!strcasecmp (atom + 1, "equire"))
 906                         return REQUIRE;
 907                 if (!strcasecmp (atom + 1, "etry"))
 908                         return RETRY;
 909                 if (!strcasecmp (atom + 1, "eturn"))
 910                         return RETURN;
 911                 if (!strcasecmp (atom + 1, "enew"))
 912                         return RENEW;
 913                 if (!strcasecmp (atom + 1, "ebind"))
 914                         return REBIND;
 915                 if (!strcasecmp (atom + 1, "eboot"))
 916                         return REBOOT;
 917                 if (!strcasecmp (atom + 1, "eject"))
 918                         return REJECT;
 919                 if (!strcasecmp (atom + 1, "everse"))
 920                         return REVERSE;
 921                 if (!strcasecmp (atom + 1, "elease"))
 922                         return RELEASE;
 923                 if (!strcasecmp (atom + 1, "efused"))
 924                         return NS_REFUSED;
 925                 if (!strcasecmp (atom + 1, "eleased"))
 926                         return TOKEN_RELEASED;
 927                 if (!strcasecmp (atom + 1, "eset"))
 928                         return TOKEN_RESET;
 929                 if (!strcasecmp (atom + 1, "eserved"))
 930                         return TOKEN_RESERVED;
 931                 if (!strcasecmp (atom + 1, "emove"))
 932                         return REMOVE;
 933                 if (!strcasecmp (atom + 1, "efresh"))
 934                         return REFRESH;
 935                 break;
 936               case 's':
 937                 if (!strcasecmp (atom + 1, "tate"))
 938                         return STATE;
 939                 if (!strcasecmp (atom + 1, "ecret"))
 940                         return SECRET;
 941                 if (!strcasecmp (atom + 1, "ervfail"))
 942                         return NS_SERVFAIL;
 943                 if (!strcasecmp (atom + 1, "witch"))
 944                         return SWITCH;
 945                 if (!strcasecmp (atom + 1, "igned"))
 946                         return SIGNED;
 947                 if (!strcasecmp (atom + 1, "tring"))
 948                         return STRING_TOKEN;
 949                 if (!strcasecmp (atom + 1, "uffix"))
 950                         return SUFFIX;
 951                 if (!strcasecmp (atom + 1, "earch"))
 952                         return SEARCH;
 953                 if (!strcasecmp (atom + 1, "tarts"))
 954                         return STARTS;
 955                 if (!strcasecmp (atom + 1, "iaddr"))
 956                         return SIADDR;
 957                 if (!strcasecmp (atom + 1, "hared-network"))
 958                         return SHARED_NETWORK;
 959                 if (!strcasecmp (atom + 1, "econdary"))
 960                         return SECONDARY;
 961                 if (!strcasecmp (atom + 1, "erver-name"))
 962                         return SERVER_NAME;
 963                 if (!strcasecmp (atom + 1, "erver-identifier"))
 964                         return SERVER_IDENTIFIER;
 965                 if (!strcasecmp (atom + 1, "erver"))
 966                         return SERVER;
 967                 if (!strcasecmp (atom + 1, "elect-timeout"))
 968                         return SELECT_TIMEOUT;
 969                 if (!strcasecmp (atom + 1, "elect"))
 970                         return SELECT;
 971                 if (!strcasecmp (atom + 1, "end"))
 972                         return SEND;
 973                 if (!strcasecmp (atom + 1, "cript"))
 974                         return SCRIPT;
 975                 if (!strcasecmp (atom + 1, "upersede"))
 976                         return SUPERSEDE;
 977                 if (!strncasecmp (atom + 1, "ub", 2)) {
 978                         if (!strcasecmp (atom + 3, "string"))
 979                                 return SUBSTRING;
 980                         if (!strcasecmp (atom + 3, "net"))
 981                                 return SUBNET;
 982                         if (!strcasecmp (atom + 3, "class"))
 983                                 return SUBCLASS;
 984                         break;
 985                 }
 986                 if (!strcasecmp (atom + 1, "pawn"))
 987                         return SPAWN;
 988                 if (!strcasecmp (atom + 1, "pace"))
 989                         return SPACE;
 990                 if (!strcasecmp (atom + 1, "tatic"))
 991                         return STATIC;
 992                 if (!strcasecmp (atom + 1, "plit"))
 993                         return SPLIT;
 994                 if (!strcasecmp (atom + 1, "et"))
 995                         return TOKEN_SET;
 996                 if (!strcasecmp (atom + 1, "econds"))
 997                         return SECONDS;
 998                 if (!strcasecmp (atom + 1, "hutdown"))
 999                         return SHUTDOWN;
1000                 if (!strcasecmp (atom + 1, "tartup"))
1001                         return STARTUP;
1002                 break;
1003               case 't':
1004                 if (!strcasecmp (atom + 1, "imestamp"))
1005                         return TIMESTAMP;
1006                 if (!strcasecmp (atom + 1, "imeout"))
1007                         return TIMEOUT;
1008                 if (!strcasecmp (atom + 1, "oken-ring"))
1009                         return TOKEN_RING;
1010                 if (!strcasecmp (atom + 1, "ext"))
1011                         return TEXT;
1012                 if (!strcasecmp (atom + 1, "stp"))
1013                         return TSTP;
1014                 if (!strcasecmp (atom + 1, "sfp"))
1015                         return TSFP;
1016                 if (!strcasecmp (atom + 1, "ransmission"))
1017                         return TRANSMISSION;
1018                 break;
1019               case 'u':
1020                 if (!strcasecmp (atom + 1, "nset"))
1021                         return UNSET;
1022                 if (!strcasecmp (atom + 1, "nsigned"))
1023                         return UNSIGNED;
1024                 if (!strcasecmp (atom + 1, "id"))
1025                         return UID;
1026                 if (!strncasecmp (atom + 1, "se", 2)) {
1027                         if (!strcasecmp (atom + 3, "r-class"))
1028                                 return USER_CLASS;
1029                         if (!strcasecmp (atom + 3, "-host-decl-names"))
1030                                 return USE_HOST_DECL_NAMES;
1031                         if (!strcasecmp (atom + 3,
1032                                          "-lease-addr-for-default-route"))
1033                                 return USE_LEASE_ADDR_FOR_DEFAULT_ROUTE;
1034                         break;
1035                 }
1036                 if (!strncasecmp (atom + 1, "nknown", 6)) {
1037                         if (!strcasecmp (atom + 7, "-clients"))
1038                                 return UNKNOWN_CLIENTS;
1039                         if (!strcasecmp (atom + 7, "-state"))
1040                                 return UNKNOWN_STATE;
1041                         if (!atom [7])
1042                                 return UNKNOWN;
1043                         break;
1044                 }
1045                 if (!strcasecmp (atom + 1, "nauthenticated"))
1046                         return AUTHENTICATED;
1047                 if (!strcasecmp (atom + 1, "pdated-dns-rr"))
1048                         return UPDATED_DNS_RR;
1049                 if (!strcasecmp (atom + 1, "pdate"))
1050                         return UPDATE;
1051                 break;
1052               case 'v':
1053                 if (!strcasecmp (atom + 1, "endor-class"))
1054                         return VENDOR_CLASS;
1055                 if (!strcasecmp (atom + 1, "endor"))
1056                         return VENDOR;
1057                 break;
1058               case 'w':
1059                 if (!strcasecmp (atom + 1, "ith"))
1060                         return WITH;
1061                 break;
1062               case 'y':
1063                 if (!strcasecmp (atom + 1, "iaddr"))
1064                         return YIADDR;
1065                 if (!strcasecmp (atom + 1, "xdomain"))
1066                         return NS_YXDOMAIN;
1067                 if (!strcasecmp (atom + 1, "xrrset"))
1068                         return NS_YXRRSET;
1069                 break;
1070               case 'z':
1071                 if (!strcasecmp (atom + 1, "one"))
1072                         return ZONE;
1073                 break;
1074         }
1075         return dfv;
1076 }