contrib/isc-dhcp/minires/res_mkupdate.c

   1 /*
   2  * Copyright (c) 1996-1999 by Internet Software Consortium.
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
   9  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  10  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  11  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  12  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  13  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  14  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  15  * SOFTWARE.
  16  */
  17
  18 /*
  19  * Based on the Dynamic DNS reference implementation by Viraj Bais
  20  * <viraj_bais@ccm.fm.intel.com>
  21  */
  22
  23 #if !defined(lint) && !defined(SABER)
  24 static const char rcsid[] = "$Id: res_mkupdate.c,v 1.7 2001/01/11 02:16:24 mellon Exp $";
  25 #endif /* not lint */
  26
  27 #include <sys/types.h>
  28 #include <sys/param.h>
  29
  30 #include <netinet/in.h>
  31 #include <arpa/inet.h>
  32 #include <sys/socket.h>
  33
  34 #include <errno.h>
  35 #include <limits.h>
  36 #include <netdb.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40 #include <unistd.h>
  41 #include <ctype.h>
  42
  43 #include "minires/minires.h"
  44 #include "arpa/nameser.h"
  45
  46 /* Options.  Leave them on. */
  47 #define DEBUG
  48 #define MAXPORT 1024
  49
  50 static int getnum_str(const u_char **, const u_char *);
  51 static int gethexnum_str(const u_char **, const u_char *);
  52 static int getword_str(char *, int,
  53                        const unsigned char **,
  54                        const unsigned char *);
  55 static int getstr_str(char *, int, const u_char **, const u_char *);
  56
  57 struct valuelist {
  58         struct valuelist *      next;
  59         struct valuelist *      prev;
  60         char *                  name;
  61         char *                  proto;
  62         int                     port;
  63 };
  64
  65 static int findservice(const char *, struct valuelist **);
  66 static struct servent *cgetservbyport(unsigned, const char *);
  67
  68 #define ShrinkBuffer(x)  if ((buflen -= x) < 0) return (-2);
  69
  70 /* Forward. */
  71
  72 int res_protocolnumber(const char *);
  73 int res_servicenumber(const char *);
  74 static struct protoent *cgetprotobynumber(int);
  75
  76 /*
  77  * Form update packets.
  78  * Returns the size of the resulting packet if no error
  79  * On error,
  80  *      returns -1 if error in reading a word/number in rdata
  81  *                 portion for update packets
  82  *              -2 if length of buffer passed is insufficient
  83  *              -3 if zone section is not the first section in
  84  *                 the linked list, or section order has a problem
  85  *              -4 on a number overflow
  86  *              -5 unknown operation or no records
  87  */
  88 int
  89 res_nmkupdate(res_state statp,
  90               ns_updrec *rrecp_in, double *bp, unsigned *blp) {
  91         ns_updrec *rrecp_start = rrecp_in;
  92         HEADER *hp;
  93         u_char *cp, *sp1, *sp2;
  94         const unsigned char *startp, *endp;
  95         int n, i, soanum, multiline;
  96         ns_updrec *rrecp;
  97         struct in_addr ina;
  98         char buf2[MAXDNAME];
  99         u_char buf3[MAXDNAME];
 100         int section, numrrs = 0, counts[ns_s_max];
 101         u_int16_t rtype, rclass;
 102         u_int32_t n1, rttl;
 103         u_char *dnptrs[20], **dpp, **lastdnptr;
 104         unsigned siglen, keylen, certlen;
 105         unsigned buflen = *blp;
 106         u_char *buf = (unsigned char *)bp;
 107
 108         /*
 109          * Initialize header fields.
 110          */
 111         if ((buf == NULL) || (buflen < HFIXEDSZ))
 112                 return -1;
 113         memset(buf, 0, HFIXEDSZ);
 114         hp = (HEADER *) buf;
 115         hp->id = htons(++statp->id);
 116         hp->opcode = ns_o_update;
 117         hp->rcode = NOERROR;
 118         sp1 = buf + 2*INT16SZ;  /* save pointer to zocount */
 119         cp = buf + HFIXEDSZ;
 120         buflen -= HFIXEDSZ;
 121         dpp = dnptrs;
 122         *dpp++ = buf;
 123         *dpp++ = NULL;
 124         lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
 125
 126         if (rrecp_start == NULL)
 127                 return (-5);
 128         else if (rrecp_start->r_section != S_ZONE)
 129                 return (-3);
 130
 131         memset(counts, 0, sizeof counts);
 132         for (rrecp = rrecp_start; rrecp; rrecp = ISC_LIST_NEXT(rrecp,
 133                                                                r_glink)) {
 134                 numrrs++;
 135                 section = rrecp->r_section;
 136                 if (section < 0 || section >= ns_s_max)
 137                         return (-1);
 138                 counts[section]++;
 139                 for (i = section + 1; i < ns_s_max; i++)
 140                         if (counts[i])
 141                                 return (-3);
 142                 rtype = rrecp->r_type;
 143                 rclass = rrecp->r_class;
 144                 rttl = rrecp->r_ttl;
 145                 /* overload class and type */
 146                 if (section == S_PREREQ) {
 147                         rttl = 0;
 148                         switch (rrecp->r_opcode) {
 149                         case YXDOMAIN:
 150                                 rclass = C_ANY;
 151                                 rtype = T_ANY;
 152                                 rrecp->r_size = 0;
 153                                 break;
 154                         case NXDOMAIN:
 155                                 rclass = C_NONE;
 156                                 rtype = T_ANY;
 157                                 rrecp->r_size = 0;
 158                                 break;
 159                         case NXRRSET:
 160                                 rclass = C_NONE;
 161                                 rrecp->r_size = 0;
 162                                 break;
 163                         case YXRRSET:
 164                                 if (rrecp->r_size == 0)
 165                                         rclass = C_ANY;
 166                                 break;
 167                         default:
 168                                 fprintf(stderr,
 169                                         "res_mkupdate: incorrect opcode: %d\n",
 170                                         rrecp->r_opcode);
 171                                 fflush(stderr);
 172                                 return (-1);
 173                         }
 174                 } else if (section == S_UPDATE) {
 175                         switch (rrecp->r_opcode) {
 176                         case DELETE:
 177                                 rclass = rrecp->r_size == 0 ? C_ANY : C_NONE;
 178                                 break;
 179                         case ADD:
 180                                 break;
 181                         default:
 182                                 fprintf(stderr,
 183                                         "res_mkupdate: incorrect opcode: %d\n",
 184                                         rrecp->r_opcode);
 185                                 fflush(stderr);
 186                                 return (-1);
 187                         }
 188                 }
 189
 190                 /*
 191                  * XXX  appending default domain to owner name is omitted,
 192                  *      fqdn must be provided
 193                  */
 194                 if ((n = dn_comp(rrecp->r_dname, cp, buflen, dnptrs,
 195                                  lastdnptr)) < 0)
 196                         return (-1);
 197                 cp += n;
 198                 ShrinkBuffer(n + 2*INT16SZ);
 199                 PUTSHORT(rtype, cp);
 200                 PUTSHORT(rclass, cp);
 201                 if (section == S_ZONE) {
 202                         if (numrrs != 1 || rrecp->r_type != T_SOA)
 203                                 return (-3);
 204                         continue;
 205                 }
 206                 ShrinkBuffer(INT32SZ + INT16SZ);
 207                 PUTLONG(rttl, cp);
 208                 sp2 = cp;  /* save pointer to length byte */
 209                 cp += INT16SZ;
 210                 if (rrecp->r_size == 0) {
 211                         if (section == S_UPDATE && rclass != C_ANY)
 212                                 return (-1);
 213                         else {
 214                                 PUTSHORT(0, sp2);
 215                                 continue;
 216                         }
 217                 }
 218                 startp = rrecp->r_data;
 219                 endp = startp + rrecp->r_size - 1;
 220                 /* XXX this should be done centrally. */
 221                 switch (rrecp->r_type) {
 222                 case T_A:
 223                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 224                                 return (-1);
 225                         if (!inet_aton(buf2, &ina))
 226                                 return (-1);
 227                         n1 = ntohl(ina.s_addr);
 228                         ShrinkBuffer(INT32SZ);
 229                         PUTLONG(n1, cp);
 230                         break;
 231                 case T_CNAME:
 232                 case T_MB:
 233                 case T_MG:
 234                 case T_MR:
 235                 case T_NS:
 236                 case T_PTR:
 237                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 238                                 return (-1);
 239                         n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 240                         if (n < 0)
 241                                 return (-1);
 242                         cp += n;
 243                         ShrinkBuffer(n);
 244                         break;
 245                 case T_MINFO:
 246                 case T_SOA:
 247                 case T_RP:
 248                         for (i = 0; i < 2; i++) {
 249                                 if (!getword_str(buf2, sizeof buf2, &startp,
 250                                                  endp))
 251                                 return (-1);
 252                                 n = dn_comp(buf2, cp, buflen,
 253                                             dnptrs, lastdnptr);
 254                                 if (n < 0)
 255                                         return (-1);
 256                                 cp += n;
 257                                 ShrinkBuffer(n);
 258                         }
 259                         if (rrecp->r_type == T_SOA) {
 260                                 ShrinkBuffer(5 * INT32SZ);
 261                                 while (isspace(*startp) || !*startp)
 262                                         startp++;
 263                                 if (*startp == '(') {
 264                                         multiline = 1;
 265                                         startp++;
 266                                 } else
 267                                         multiline = 0;
 268                                 /* serial, refresh, retry, expire, minimum */
 269                                 for (i = 0; i < 5; i++) {
 270                                         soanum = getnum_str(&startp, endp);
 271                                         if (soanum < 0)
 272                                                 return (-1);
 273                                         PUTLONG(soanum, cp);
 274                                 }
 275                                 if (multiline) {
 276                                         while (isspace(*startp) || !*startp)
 277                                                 startp++;
 278                                         if (*startp != ')')
 279                                                 return (-1);
 280                                 }
 281                         }
 282                         break;
 283                 case T_MX:
 284                 case T_AFSDB:
 285                 case T_RT:
 286                         n = getnum_str(&startp, endp);
 287                         if (n < 0)
 288                                 return (-1);
 289                         ShrinkBuffer(INT16SZ);
 290                         PUTSHORT(n, cp);
 291                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 292                                 return (-1);
 293                         n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 294                         if (n < 0)
 295                                 return (-1);
 296                         cp += n;
 297                         ShrinkBuffer(n);
 298                         break;
 299                 case T_SRV:
 300                         n = getnum_str(&startp, endp);
 301                         if (n < 0)
 302                                 return (-1);
 303                         ShrinkBuffer(INT16SZ);
 304                         PUTSHORT(n, cp);
 305
 306                         n = getnum_str(&startp, endp);
 307                         if (n < 0)
 308                                 return (-1);
 309                         ShrinkBuffer(INT16SZ);
 310                         PUTSHORT(n, cp);
 311
 312                         n = getnum_str(&startp, endp);
 313                         if (n < 0)
 314                                 return (-1);
 315                         ShrinkBuffer(INT16SZ);
 316                         PUTSHORT(n, cp);
 317
 318                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 319                                 return (-1);
 320                         n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 321                         if (n < 0)
 322                                 return (-1);
 323                         cp += n;
 324                         ShrinkBuffer(n);
 325                         break;
 326                 case T_PX:
 327                         n = getnum_str(&startp, endp);
 328                         if (n < 0)
 329                                 return (-1);
 330                         PUTSHORT(n, cp);
 331                         ShrinkBuffer(INT16SZ);
 332                         for (i = 0; i < 2; i++) {
 333                                 if (!getword_str(buf2, sizeof buf2, &startp,
 334                                                  endp))
 335                                         return (-1);
 336                                 n = dn_comp(buf2, cp, buflen, dnptrs,
 337                                             lastdnptr);
 338                                 if (n < 0)
 339                                         return (-1);
 340                                 cp += n;
 341                                 ShrinkBuffer(n);
 342                         }
 343                         break;
 344                 case T_WKS: {
 345                         char bm[MAXPORT/8];
 346                         unsigned maxbm = 0;
 347
 348                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 349                                 return (-1);
 350                         if (!inet_aton(buf2, &ina))
 351                                 return (-1);
 352                         n1 = ntohl(ina.s_addr);
 353                         ShrinkBuffer(INT32SZ);
 354                         PUTLONG(n1, cp);
 355
 356                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 357                                 return (-1);
 358                         if ((i = res_protocolnumber(buf2)) < 0)
 359                                 return (-1);
 360                         ShrinkBuffer(1);
 361                         *cp++ = i & 0xff;
 362
 363                         for (i = 0; i < MAXPORT/8 ; i++)
 364                                 bm[i] = 0;
 365
 366                         while (getword_str(buf2, sizeof buf2, &startp, endp)) {
 367                                 if ((n1 = res_servicenumber(buf2)) <= 0)
 368                                         return (-1);
 369
 370                                 if (n1 < MAXPORT) {
 371                                         bm[n1/8] |= (0x80>>(n1%8));
 372                                         if (n1 > maxbm)
 373                                                 maxbm = n1;
 374                                 } else
 375                                         return (-1);
 376                         }
 377                         maxbm = maxbm/8 + 1;
 378                         ShrinkBuffer(maxbm);
 379                         memcpy(cp, bm, maxbm);
 380                         cp += maxbm;
 381                         break;
 382                 }
 383                 case T_HINFO:
 384                         for (i = 0; i < 2; i++) {
 385                                 if ((n = getstr_str(buf2, sizeof buf2,
 386                                                 &startp, endp)) < 0)
 387                                         return (-1);
 388                                 if (n > 255)
 389                                         return (-1);
 390                                 ShrinkBuffer(n+1);
 391                                 *cp++ = n;
 392                                 memcpy(cp, buf2, (unsigned)n);
 393                                 cp += n;
 394                         }
 395                         break;
 396                 case T_TXT:
 397                         while (1) {
 398                                 if ((n = getstr_str(buf2, sizeof buf2,
 399                                                 &startp, endp)) < 0) {
 400                                         if (cp != (sp2 + INT16SZ))
 401                                                 break;
 402                                         return (-1);
 403                                 }
 404                                 if (n > 255)
 405                                         return (-1);
 406                                 ShrinkBuffer(n+1);
 407                                 *cp++ = n;
 408                                 memcpy(cp, buf2, (unsigned)n);
 409                                 cp += n;
 410                         }
 411                         break;
 412                 case T_X25:
 413                         /* RFC 1183 */
 414                         if ((n = getstr_str(buf2, sizeof buf2, &startp,
 415                                          endp)) < 0)
 416                                 return (-1);
 417                         if (n > 255)
 418                                 return (-1);
 419                         ShrinkBuffer(n+1);
 420                         *cp++ = n;
 421                         memcpy(cp, buf2, (unsigned)n);
 422                         cp += n;
 423                         break;
 424                 case T_ISDN:
 425                         /* RFC 1183 */
 426                         if ((n = getstr_str(buf2, sizeof buf2, &startp,
 427                                          endp)) < 0)
 428                                 return (-1);
 429                         if ((n > 255) || (n == 0))
 430                                 return (-1);
 431                         ShrinkBuffer(n+1);
 432                         *cp++ = n;
 433                         memcpy(cp, buf2, (unsigned)n);
 434                         cp += n;
 435                         if ((n = getstr_str(buf2, sizeof buf2, &startp,
 436                                          endp)) < 0)
 437                                 n = 0;
 438                         if (n > 255)
 439                                 return (-1);
 440                         ShrinkBuffer(n+1);
 441                         *cp++ = n;
 442                         memcpy(cp, buf2, (unsigned)n);
 443                         cp += n;
 444                         break;
 445 #if 0
 446                 case T_NSAP:
 447                         if ((n = inet_nsap_addr((char *)startp, (u_char *)buf2, sizeof(buf2))) != 0) {
 448                                 ShrinkBuffer(n);
 449                                 memcpy(cp, buf2, n);
 450                                 cp += n;
 451                         } else {
 452                                 return (-1);
 453                         }
 454                         break;
 455                 case T_LOC:
 456                         if ((n = loc_aton((char *)startp, (u_char *)buf2)) != 0) {
 457                                 ShrinkBuffer(n);
 458                                 memcpy(cp, buf2, n);
 459                                 cp += n;
 460                         } else
 461                                 return (-1);
 462                         break;
 463                 case ns_t_sig:
 464                     {
 465                         int sig_type, success, dateerror;
 466                         u_int32_t exptime, timesigned;
 467
 468                         /* type */
 469                         if ((n = getword_str(buf2, sizeof buf2,
 470                                              &startp, endp)) < 0)
 471                                 return (-1);
 472                         sig_type = sym_ston(__p_type_syms, buf2, &success);
 473                         if (!success || sig_type == ns_t_any)
 474                                 return (-1);
 475                         ShrinkBuffer(INT16SZ);
 476                         PUTSHORT(sig_type, cp);
 477                         /* alg */
 478                         n = getnum_str(&startp, endp);
 479                         if (n < 0)
 480                                 return (-1);
 481                         ShrinkBuffer(1);
 482                         *cp++ = n;
 483                         /* labels */
 484                         n = getnum_str(&startp, endp);
 485                         if (n <= 0 || n > 255)
 486                                 return (-1);
 487                         ShrinkBuffer(1);
 488                         *cp++ = n;
 489                         /* ottl  & expire */
 490                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 491                                 return (-1);
 492                         exptime = ns_datetosecs(buf2, &dateerror);
 493                         if (!dateerror) {
 494                                 ShrinkBuffer(INT32SZ);
 495                                 PUTLONG(rttl, cp);
 496                         }
 497                         else {
 498                                 char *ulendp;
 499                                 u_int32_t ottl;
 500
 501                                 ottl = strtoul(buf2, &ulendp, 10);
 502                                 if (ulendp != NULL && *ulendp != '\0')
 503                                         return (-1);
 504                                 ShrinkBuffer(INT32SZ);
 505                                 PUTLONG(ottl, cp);
 506                                 if (!getword_str(buf2, sizeof buf2, &startp,
 507                                                  endp))
 508                                         return (-1);
 509                                 exptime = ns_datetosecs(buf2, &dateerror);
 510                                 if (dateerror)
 511                                         return (-1);
 512                         }
 513                         /* expire */
 514                         ShrinkBuffer(INT32SZ);
 515                         PUTLONG(exptime, cp);
 516                         /* timesigned */
 517                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 518                                 return (-1);
 519                         timesigned = ns_datetosecs(buf2, &dateerror);
 520                         if (!dateerror) {
 521                                 ShrinkBuffer(INT32SZ);
 522                                 PUTLONG(timesigned, cp);
 523                         }
 524                         else
 525                                 return (-1);
 526                         /* footprint */
 527                         n = getnum_str(&startp, endp);
 528                         if (n < 0)
 529                                 return (-1);
 530                         ShrinkBuffer(INT16SZ);
 531                         PUTSHORT(n, cp);
 532                         /* signer name */
 533                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 534                                 return (-1);
 535                         n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 536                         if (n < 0)
 537                                 return (-1);
 538                         cp += n;
 539                         ShrinkBuffer(n);
 540                         /* sig */
 541                         if ((n = getword_str(buf2, sizeof buf2,
 542                                              &startp, endp)) < 0)
 543                                 return (-1);
 544                         siglen = b64_pton(buf2, buf3, sizeof(buf3));
 545                         if (siglen < 0)
 546                                 return (-1);
 547                         ShrinkBuffer(siglen);
 548                         memcpy(cp, buf3, siglen);
 549                         cp += siglen;
 550                         break;
 551                     }
 552                 case ns_t_key:
 553                         /* flags */
 554                         n = gethexnum_str(&startp, endp);
 555                         if (n < 0)
 556                                 return (-1);
 557                         ShrinkBuffer(INT16SZ);
 558                         PUTSHORT(n, cp);
 559                         /* proto */
 560                         n = getnum_str(&startp, endp);
 561                         if (n < 0)
 562                                 return (-1);
 563                         ShrinkBuffer(1);
 564                         *cp++ = n;
 565                         /* alg */
 566                         n = getnum_str(&startp, endp);
 567                         if (n < 0)
 568                                 return (-1);
 569                         ShrinkBuffer(1);
 570                         *cp++ = n;
 571                         /* key */
 572                         if ((n = getword_str(buf2, sizeof buf2,
 573                                              &startp, endp)) < 0)
 574                                 return (-1);
 575                         keylen = b64_pton(buf2, buf3, sizeof(buf3));
 576                         if (keylen < 0)
 577                                 return (-1);
 578                         ShrinkBuffer(keylen);
 579                         memcpy(cp, buf3, keylen);
 580                         cp += keylen;
 581                         break;
 582                 case ns_t_nxt:
 583                     {
 584                         int success, nxt_type;
 585                         u_char data[32];
 586                         int maxtype;
 587
 588                         /* next name */
 589                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 590                                 return (-1);
 591                         n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 592                         if (n < 0)
 593                                 return (-1);
 594                         cp += n;
 595                         ShrinkBuffer(n);
 596                         maxtype = 0;
 597                         memset(data, 0, sizeof data);
 598                         while (1) {
 599                                 if (!getword_str(buf2, sizeof buf2, &startp,
 600                                                  endp))
 601                                         break;
 602                                 nxt_type = sym_ston(__p_type_syms, buf2,
 603                                                     &success);
 604                                 if (!success || !ns_t_rr_p(nxt_type))
 605                                         return (-1);
 606                                 NS_NXT_BIT_SET(nxt_type, data);
 607                                 if (nxt_type > maxtype)
 608                                         maxtype = nxt_type;
 609                         }
 610                         n = maxtype/NS_NXT_BITS+1;
 611                         ShrinkBuffer(n);
 612                         memcpy(cp, data, n);
 613                         cp += n;
 614                         break;
 615                     }
 616                 case ns_t_cert:
 617                         /* type */
 618                         n = getnum_str(&startp, endp);
 619                         if (n < 0)
 620                                 return (-1);
 621                         ShrinkBuffer(INT16SZ);
 622                         PUTSHORT(n, cp);
 623                         /* key tag */
 624                         n = getnum_str(&startp, endp);
 625                         if (n < 0)
 626                                 return (-1);
 627                         ShrinkBuffer(INT16SZ);
 628                         PUTSHORT(n, cp);
 629                         /* alg */
 630                         n = getnum_str(&startp, endp);
 631                         if (n < 0)
 632                                 return (-1);
 633                         ShrinkBuffer(1);
 634                         *cp++ = n;
 635                         /* cert */
 636                         if ((n = getword_str(buf2, sizeof buf2,
 637                                              &startp, endp)) < 0)
 638                                 return (-1);
 639                         certlen = b64_pton(buf2, buf3, sizeof(buf3));
 640                         if (certlen < 0)
 641                                 return (-1);
 642                         ShrinkBuffer(certlen);
 643                         memcpy(cp, buf3, certlen);
 644                         cp += certlen;
 645                         break;
 646 #endif
 647                 default:
 648                         return (-1);
 649                 } /*switch*/
 650                 n = (u_int16_t)((cp - sp2) - INT16SZ);
 651                 PUTSHORT(n, sp2);
 652         } /*for*/
 653
 654         hp->qdcount = htons(counts[0]);
 655         hp->ancount = htons(counts[1]);
 656         hp->nscount = htons(counts[2]);
 657         hp->arcount = htons(counts[3]);
 658         *blp = cp - buf;
 659         return 0;
 660 }
 661
 662 /*
 663  * Get a whitespace delimited word from a string (not file)
 664  * into buf. modify the start pointer to point after the
 665  * word in the string.
 666  */
 667 static int
 668 getword_str(char *buf, int size, const u_char **startpp, const u_char *endp) {
 669         char *cp;
 670         int c;
 671
 672         for (cp = buf; *startpp <= endp; ) {
 673                 c = **startpp;
 674                 if (isspace(c) || c == '\0') {
 675                         if (cp != buf) /* trailing whitespace */
 676                                 break;
 677                         else { /* leading whitespace */
 678                                 (*startpp)++;
 679                                 continue;
 680                         }
 681                 }
 682                 (*startpp)++;
 683                 if (cp >= buf+size-1)
 684                         break;
 685                 *cp++ = (u_char)c;
 686         }
 687         *cp = '\0';
 688         return (cp != buf);
 689 }
 690
 691 /*
 692  * get a white spae delimited string from memory.  Process quoted strings
 693  * and \DDD escapes.  Return length or -1 on error.  Returned string may
 694  * contain nulls.
 695  */
 696 static char digits[] = "0123456789";
 697 static int
 698 getstr_str(char *buf, int size, const u_char **startpp, const u_char *endp) {
 699         char *cp;
 700         int c, c1 = 0;
 701         int inquote = 0;
 702         int seen_quote = 0;
 703         int escape = 0;
 704         int dig = 0;
 705
 706         for (cp = buf; *startpp <= endp; ) {
 707                 if ((c = **startpp) == '\0')
 708                         break;
 709                 /* leading white space */
 710                 if ((cp == buf) && !seen_quote && isspace(c)) {
 711                         (*startpp)++;
 712                         continue;
 713                 }
 714
 715                 switch (c) {
 716                 case '\\':
 717                         if (!escape)  {
 718                                 escape = 1;
 719                                 dig = 0;
 720                                 c1 = 0;
 721                                 (*startpp)++;
 722                                 continue;
 723                         }
 724                         goto do_escape;
 725                 case '"':
 726                         if (!escape) {
 727                                 inquote = !inquote;
 728                                 seen_quote = 1;
 729                                 (*startpp)++;
 730                                 continue;
 731                         }
 732                         /* fall through */
 733                 default:
 734                 do_escape:
 735                         if (escape) {
 736                                 switch (c) {
 737                                 case '0':
 738                                 case '1':
 739                                 case '2':
 740                                 case '3':
 741                                 case '4':
 742                                 case '5':
 743                                 case '6':
 744                                 case '7':
 745                                 case '8':
 746                                 case '9':
 747                                         c1 = c1 * 10 +
 748                                                 (strchr(digits, c) - digits);
 749
 750                                         if (++dig == 3) {
 751                                                 c = c1 &0xff;
 752                                                 break;
 753                                         }
 754                                         (*startpp)++;
 755                                         continue;
 756                                 }
 757                                 escape = 0;
 758                         } else if (!inquote && isspace(c))
 759                                 goto done;
 760                         if (cp >= buf+size-1)
 761                                 goto done;
 762                         *cp++ = (u_char)c;
 763                         (*startpp)++;
 764                 }
 765         }
 766  done:
 767         *cp = '\0';
 768         return ((cp == buf)?  (seen_quote? 0: -1): (cp - buf));
 769 }
 770 /*
 771  * Get a whitespace delimited base 16 number from a string (not file) into buf
 772  * update the start pointer to point after the number in the string.
 773  */
 774 static int
 775 gethexnum_str(const u_char **startpp, const u_char *endp) {
 776         int c, n;
 777         int seendigit = 0;
 778         int m = 0;
 779
 780         if (*startpp + 2 >= endp ||
 781             strncasecmp((const char *)*startpp, "0x", 2) != 0)
 782                 return getnum_str(startpp, endp);
 783         (*startpp)+=2;
 784         for (n = 0; *startpp <= endp; ) {
 785                 c = **startpp;
 786                 if (isspace(c) || c == '\0') {
 787                         if (seendigit) /* trailing whitespace */
 788                                 break;
 789                         else { /* leading whitespace */
 790                                 (*startpp)++;
 791                                 continue;
 792                         }
 793                 }
 794                 if (c == ';') {
 795                         while ((*startpp <= endp) &&
 796                                ((c = **startpp) != '\n'))
 797                                         (*startpp)++;
 798                         if (seendigit)
 799                                 break;
 800                         continue;
 801                 }
 802                 if (!isxdigit(c)) {
 803                         if (c == ')' && seendigit) {
 804                                 (*startpp)--;
 805                                 break;
 806                         }
 807                         return (-1);
 808                 }
 809                 (*startpp)++;
 810                 if (isdigit(c))
 811                         n = n * 16 + (c - '0');
 812                 else
 813                         n = n * 16 + (tolower(c) - 'a' + 10);
 814                 seendigit = 1;
 815         }
 816         return (n + m);
 817 }
 818
 819 /*
 820  * Get a whitespace delimited base 16 number from a string (not file) into buf
 821  * update the start pointer to point after the number in the string.
 822  */
 823 static int
 824 getnum_str(const u_char **startpp, const u_char *endp) {
 825         int c, n;
 826         int seendigit = 0;
 827         int m = 0;
 828
 829         for (n = 0; *startpp <= endp; ) {
 830                 c = **startpp;
 831                 if (isspace(c) || c == '\0') {
 832                         if (seendigit) /* trailing whitespace */
 833                                 break;
 834                         else { /* leading whitespace */
 835                                 (*startpp)++;
 836                                 continue;
 837                         }
 838                 }
 839                 if (c == ';') {
 840                         while ((*startpp <= endp) &&
 841                                ((c = **startpp) != '\n'))
 842                                         (*startpp)++;
 843                         if (seendigit)
 844                                 break;
 845                         continue;
 846                 }
 847                 if (!isdigit(c)) {
 848                         if (c == ')' && seendigit) {
 849                                 (*startpp)--;
 850                                 break;
 851                         }
 852                         return (-1);
 853                 }
 854                 (*startpp)++;
 855                 n = n * 10 + (c - '0');
 856                 seendigit = 1;
 857         }
 858         return (n + m);
 859 }
 860
 861 /*
 862  * Allocate a resource record buffer & save rr info.
 863  */
 864 ns_updrec *
 865 res_mkupdrec(int section, const char *dname,
 866              u_int class, u_int type, u_long ttl) {
 867         ns_updrec *rrecp = (ns_updrec *)calloc(1, sizeof(ns_updrec));
 868
 869         if (!rrecp || !(rrecp->r_dname = strdup(dname))) {
 870                 if (rrecp)
 871                         free((char *)rrecp);
 872                 return (NULL);
 873         }
 874         rrecp->r_class = class;
 875         rrecp->r_type = type;
 876         rrecp->r_ttl = ttl;
 877         rrecp->r_section = section;
 878         return (rrecp);
 879 }
 880
 881 /*
 882  * Free a resource record buffer created by res_mkupdrec.
 883  */
 884 void
 885 res_freeupdrec(ns_updrec *rrecp) {
 886         /* Note: freeing r_dp is the caller's responsibility. */
 887         if (rrecp->r_dname != NULL)
 888                 free(rrecp->r_dname);
 889         free(rrecp);
 890 }
 891
 892 static struct valuelist *servicelist, *protolist;
 893
 894 void
 895 res_buildservicelist() {
 896         struct servent *sp;
 897         struct valuelist *slp;
 898
 899 #ifdef MAYBE_HESIOD
 900         setservent(0);
 901 #else
 902         setservent(1);
 903 #endif
 904         while ((sp = getservent()) != NULL) {
 905                 slp = (struct valuelist *)malloc(sizeof(struct valuelist));
 906                 if (!slp)
 907                         break;
 908                 slp->name = strdup(sp->s_name);
 909                 slp->proto = strdup(sp->s_proto);
 910                 if ((slp->name == NULL) || (slp->proto == NULL)) {
 911                         if (slp->name) free(slp->name);
 912                         if (slp->proto) free(slp->proto);
 913                         free(slp);
 914                         break;
 915                 }
 916                 slp->port = ntohs((u_int16_t)sp->s_port);  /* host byt order */
 917                 slp->next = servicelist;
 918                 slp->prev = NULL;
 919                 if (servicelist)
 920                         servicelist->prev = slp;
 921                 servicelist = slp;
 922         }
 923         endservent();
 924 }
 925
 926 void
 927 res_destroyservicelist() {
 928         struct valuelist *slp, *slp_next;
 929
 930         for (slp = servicelist; slp != NULL; slp = slp_next) {
 931                 slp_next = slp->next;
 932                 free(slp->name);
 933                 free(slp->proto);
 934                 free(slp);
 935         }
 936         servicelist = (struct valuelist *)0;
 937 }
 938
 939 void
 940 res_buildprotolist() {
 941         struct protoent *pp;
 942         struct valuelist *slp;
 943
 944 #ifdef MAYBE_HESIOD
 945         setprotoent(0);
 946 #else
 947         setprotoent(1);
 948 #endif
 949         while ((pp = getprotoent()) != NULL) {
 950                 slp = (struct valuelist *)malloc(sizeof(struct valuelist));
 951                 if (!slp)
 952                         break;
 953                 slp->name = strdup(pp->p_name);
 954                 if (slp->name == NULL) {
 955                         free(slp);
 956                         break;
 957                 }
 958                 slp->port = pp->p_proto;        /* host byte order */
 959                 slp->next = protolist;
 960                 slp->prev = NULL;
 961                 if (protolist)
 962                         protolist->prev = slp;
 963                 protolist = slp;
 964         }
 965         endprotoent();
 966 }
 967
 968 void
 969 res_destroyprotolist() {
 970         struct valuelist *plp, *plp_next;
 971
 972         for (plp = protolist; plp != NULL; plp = plp_next) {
 973                 plp_next = plp->next;
 974                 free(plp->name);
 975                 free(plp);
 976         }
 977         protolist = (struct valuelist *)0;
 978 }
 979
 980 static int
 981 findservice(const char *s, struct valuelist **list) {
 982         struct valuelist *lp = *list;
 983         int n;
 984
 985         for (; lp != NULL; lp = lp->next)
 986                 if (strcasecmp(lp->name, s) == 0) {
 987                         if (lp != *list) {
 988                                 lp->prev->next = lp->next;
 989                                 if (lp->next)
 990                                         lp->next->prev = lp->prev;
 991                                 (*list)->prev = lp;
 992                                 lp->next = *list;
 993                                 *list = lp;
 994                         }
 995                         return (lp->port);      /* host byte order */
 996                 }
 997         if (sscanf(s, "%d", &n) != 1 || n <= 0)
 998                 n = -1;
 999         return (n);
1000 }
1001
1002 /*
1003  * Convert service name or (ascii) number to int.
1004  */
1005 int
1006 res_servicenumber(const char *p) {
1007         if (servicelist == (struct valuelist *)0)
1008                 res_buildservicelist();
1009         return (findservice(p, &servicelist));
1010 }
1011
1012 /*
1013  * Convert protocol name or (ascii) number to int.
1014  */
1015 int
1016 res_protocolnumber(const char *p) {
1017         if (protolist == (struct valuelist *)0)
1018                 res_buildprotolist();
1019         return (findservice(p, &protolist));
1020 }
1021
1022 static struct servent *
1023 cgetservbyport(unsigned port, const char *proto) {      /* Host byte order. */
1024         struct valuelist **list = &servicelist;
1025         struct valuelist *lp = *list;
1026         static struct servent serv;
1027
1028         port = ntohs(port);
1029         for (; lp != NULL; lp = lp->next) {
1030                 if (port != (u_int16_t)lp->port)        /* Host byte order. */
1031                         continue;
1032                 if (strcasecmp(lp->proto, proto) == 0) {
1033                         if (lp != *list) {
1034                                 lp->prev->next = lp->next;
1035                                 if (lp->next)
1036                                         lp->next->prev = lp->prev;
1037                                 (*list)->prev = lp;
1038                                 lp->next = *list;
1039                                 *list = lp;
1040                         }
1041                         serv.s_name = lp->name;
1042                         serv.s_port = htons((u_int16_t)lp->port);
1043                         serv.s_proto = lp->proto;
1044                         return (&serv);
1045                 }
1046         }
1047         return (0);
1048 }
1049
1050 static struct protoent *
1051 cgetprotobynumber(int proto) {                          /* Host byte order. */
1052         struct valuelist **list = &protolist;
1053         struct valuelist *lp = *list;
1054         static struct protoent prot;
1055
1056         for (; lp != NULL; lp = lp->next)
1057                 if (lp->port == proto) {                /* Host byte order. */
1058                         if (lp != *list) {
1059                                 lp->prev->next = lp->next;
1060                                 if (lp->next)
1061                                         lp->next->prev = lp->prev;
1062                                 (*list)->prev = lp;
1063                                 lp->next = *list;
1064                                 *list = lp;
1065                         }
1066                         prot.p_name = lp->name;
1067                         prot.p_proto = lp->port;        /* Host byte order. */
1068                         return (&prot);
1069                 }
1070         return (0);
1071 }
1072
1073 const char *
1074 res_protocolname(int num) {
1075         static char number[8];
1076         struct protoent *pp;
1077
1078         if (protolist == (struct valuelist *)0)
1079                 res_buildprotolist();
1080         pp = cgetprotobynumber(num);
1081         if (pp == 0)  {
1082                 (void) sprintf(number, "%d", num);
1083                 return (number);
1084         }
1085         return (pp->p_name);
1086 }
1087
1088 const char *
1089 res_servicename(u_int16_t port, const char *proto) {    /* Host byte order. */
1090         static char number[8];
1091         struct servent *ss;
1092
1093         if (servicelist == (struct valuelist *)0)
1094                 res_buildservicelist();
1095         ss = cgetservbyport(htons(port), proto);
1096         if (ss == 0)  {
1097                 (void) sprintf(number, "%d", port);
1098                 return (number);
1099         }
1100         return (ss->s_name);
1101 }