lib/libc/resolv/res_mkupdate.c

   1 /*-
   2  * SPDX-License-Identifier: ISC
   3  *
   4  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (c) 1996-1999 by Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  13  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  17  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /*! \file
  21  * \brief
  22  * Based on the Dynamic DNS reference implementation by Viraj Bais
  23  * &lt;viraj_bais@ccm.fm.intel.com>
  24  */
  25
  26 #include "port_before.h"
  27
  28 #include <sys/param.h>
  29
  30 #include <netinet/in.h>
  31 #include <arpa/nameser.h>
  32 #include <arpa/inet.h>
  33
  34 #include <errno.h>
  35 #include <limits.h>
  36 #include <netdb.h>
  37 #include <resolv.h>
  38 #include <res_update.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <unistd.h>
  43 #include <ctype.h>
  44
  45 #ifdef _LIBC
  46 #include <isc/list.h>
  47 #endif
  48
  49 #include "port_after.h"
  50
  51 /* Options.  Leave them on. */
  52 #ifndef DEBUG
  53 #define DEBUG
  54 #endif
  55 #define MAXPORT 1024
  56
  57 static int getnum_str(u_char **, u_char *);
  58 static int gethexnum_str(u_char **, u_char *);
  59 static int getword_str(char *, int, u_char **, u_char *);
  60 static int getstr_str(char *, int, u_char **, u_char *);
  61
  62 #define ShrinkBuffer(x)  if ((buflen -= x) < 0) return (-2);
  63
  64 /* Forward. */
  65
  66 #ifdef _LIBC
  67 static
  68 #endif
  69 int res_protocolnumber(const char *);
  70 #ifdef _LIBC
  71 static
  72 #endif
  73 int res_servicenumber(const char *);
  74
  75 /*%
  76  * Form update packets.
  77  * Returns the size of the resulting packet if no error
  78  *
  79  * On error,
  80  *      returns
  81  *\li              -1 if error in reading a word/number in rdata
  82  *                 portion for update packets
  83  *\li           -2 if length of buffer passed is insufficient
  84  *\li           -3 if zone section is not the first section in
  85  *                 the linked list, or section order has a problem
  86  *\li           -4 on a number overflow
  87  *\li           -5 unknown operation or no records
  88  */
  89 int
  90 res_nmkupdate(res_state statp, ns_updrec *rrecp_in, u_char *buf, int buflen) {
  91         ns_updrec *rrecp_start = rrecp_in;
  92         HEADER *hp;
  93         u_char *cp, *sp2, *startp, *endp;
  94         int n, i, soanum, multiline;
  95         ns_updrec *rrecp;
  96         struct in_addr ina;
  97         struct in6_addr in6a;
  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 #ifndef _LIBC
 105         int siglen;
 106 #endif
 107         int keylen, certlen;
 108
 109         /*
 110          * Initialize header fields.
 111          */
 112         if ((buf == NULL) || (buflen < HFIXEDSZ))
 113                 return (-1);
 114         memset(buf, 0, HFIXEDSZ);
 115         hp = (HEADER *) buf;
 116         statp->id = res_nrandomid(statp);
 117         hp->id = htons(statp->id);
 118         hp->opcode = ns_o_update;
 119         hp->rcode = NOERROR;
 120         cp = buf + HFIXEDSZ;
 121         buflen -= HFIXEDSZ;
 122         dpp = dnptrs;
 123         *dpp++ = buf;
 124         *dpp++ = NULL;
 125         lastdnptr = dnptrs + nitems(dnptrs);
 126
 127         if (rrecp_start == NULL)
 128                 return (-5);
 129         else if (rrecp_start->r_section != S_ZONE)
 130                 return (-3);
 131
 132         memset(counts, 0, sizeof counts);
 133         for (rrecp = rrecp_start; rrecp; rrecp = NEXT(rrecp, 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                 case ns_t_dname:
 238                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 239                                 return (-1);
 240                         n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 241                         if (n < 0)
 242                                 return (-1);
 243                         cp += n;
 244                         ShrinkBuffer(n);
 245                         break;
 246                 case T_MINFO:
 247                 case T_SOA:
 248                 case T_RP:
 249                         for (i = 0; i < 2; i++) {
 250                                 if (!getword_str(buf2, sizeof buf2, &startp,
 251                                                  endp))
 252                                 return (-1);
 253                                 n = dn_comp(buf2, cp, buflen,
 254                                             dnptrs, lastdnptr);
 255                                 if (n < 0)
 256                                         return (-1);
 257                                 cp += n;
 258                                 ShrinkBuffer(n);
 259                         }
 260                         if (rrecp->r_type == T_SOA) {
 261                                 ShrinkBuffer(5 * INT32SZ);
 262                                 while (isspace(*startp) || !*startp)
 263                                         startp++;
 264                                 if (*startp == '(') {
 265                                         multiline = 1;
 266                                         startp++;
 267                                 } else
 268                                         multiline = 0;
 269                                 /* serial, refresh, retry, expire, minimum */
 270                                 for (i = 0; i < 5; i++) {
 271                                         soanum = getnum_str(&startp, endp);
 272                                         if (soanum < 0)
 273                                                 return (-1);
 274                                         PUTLONG(soanum, cp);
 275                                 }
 276                                 if (multiline) {
 277                                         while (isspace(*startp) || !*startp)
 278                                                 startp++;
 279                                         if (*startp != ')')
 280                                                 return (-1);
 281                                 }
 282                         }
 283                         break;
 284                 case T_MX:
 285                 case T_AFSDB:
 286                 case T_RT:
 287                         n = getnum_str(&startp, endp);
 288                         if (n < 0)
 289                                 return (-1);
 290                         ShrinkBuffer(INT16SZ);
 291                         PUTSHORT(n, cp);
 292                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 293                                 return (-1);
 294                         n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 295                         if (n < 0)
 296                                 return (-1);
 297                         cp += n;
 298                         ShrinkBuffer(n);
 299                         break;
 300                 case T_SRV:
 301                         n = getnum_str(&startp, endp);
 302                         if (n < 0)
 303                                 return (-1);
 304                         ShrinkBuffer(INT16SZ);
 305                         PUTSHORT(n, cp);
 306
 307                         n = getnum_str(&startp, endp);
 308                         if (n < 0)
 309                                 return (-1);
 310                         ShrinkBuffer(INT16SZ);
 311                         PUTSHORT(n, cp);
 312
 313                         n = getnum_str(&startp, endp);
 314                         if (n < 0)
 315                                 return (-1);
 316                         ShrinkBuffer(INT16SZ);
 317                         PUTSHORT(n, cp);
 318
 319                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 320                                 return (-1);
 321                         n = dn_comp(buf2, cp, buflen, NULL, NULL);
 322                         if (n < 0)
 323                                 return (-1);
 324                         cp += n;
 325                         ShrinkBuffer(n);
 326                         break;
 327                 case T_PX:
 328                         n = getnum_str(&startp, endp);
 329                         if (n < 0)
 330                                 return (-1);
 331                         PUTSHORT(n, cp);
 332                         ShrinkBuffer(INT16SZ);
 333                         for (i = 0; i < 2; i++) {
 334                                 if (!getword_str(buf2, sizeof buf2, &startp,
 335                                                  endp))
 336                                         return (-1);
 337                                 n = dn_comp(buf2, cp, buflen, dnptrs,
 338                                             lastdnptr);
 339                                 if (n < 0)
 340                                         return (-1);
 341                                 cp += n;
 342                                 ShrinkBuffer(n);
 343                         }
 344                         break;
 345                 case T_WKS: {
 346                         char bm[MAXPORT/8];
 347                         unsigned int maxbm = 0;
 348
 349                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 350                                 return (-1);
 351                         if (!inet_aton(buf2, &ina))
 352                                 return (-1);
 353                         n1 = ntohl(ina.s_addr);
 354                         ShrinkBuffer(INT32SZ);
 355                         PUTLONG(n1, cp);
 356
 357                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 358                                 return (-1);
 359                         if ((i = res_protocolnumber(buf2)) < 0)
 360                                 return (-1);
 361                         ShrinkBuffer(1);
 362                         *cp++ = i & 0xff;
 363
 364                         for (i = 0; i < MAXPORT/8 ; i++)
 365                                 bm[i] = 0;
 366
 367                         while (getword_str(buf2, sizeof buf2, &startp, endp)) {
 368                                 if ((n = res_servicenumber(buf2)) <= 0)
 369                                         return (-1);
 370
 371                                 if (n < MAXPORT) {
 372                                         bm[n/8] |= (0x80>>(n%8));
 373                                         if ((unsigned)n > maxbm)
 374                                                 maxbm = n;
 375                                 } else
 376                                         return (-1);
 377                         }
 378                         maxbm = maxbm/8 + 1;
 379                         ShrinkBuffer(maxbm);
 380                         memcpy(cp, bm, maxbm);
 381                         cp += maxbm;
 382                         break;
 383                 }
 384                 case T_HINFO:
 385                         for (i = 0; i < 2; i++) {
 386                                 if ((n = getstr_str(buf2, sizeof buf2,
 387                                                 &startp, endp)) < 0)
 388                                         return (-1);
 389                                 if (n > 255)
 390                                         return (-1);
 391                                 ShrinkBuffer(n+1);
 392                                 *cp++ = n;
 393                                 memcpy(cp, buf2, n);
 394                                 cp += n;
 395                         }
 396                         break;
 397                 case T_TXT:
 398                         for (;;) {
 399                                 if ((n = getstr_str(buf2, sizeof buf2,
 400                                                 &startp, endp)) < 0) {
 401                                         if (cp != (sp2 + INT16SZ))
 402                                                 break;
 403                                         return (-1);
 404                                 }
 405                                 if (n > 255)
 406                                         return (-1);
 407                                 ShrinkBuffer(n+1);
 408                                 *cp++ = n;
 409                                 memcpy(cp, buf2, n);
 410                                 cp += n;
 411                         }
 412                         break;
 413                 case T_X25:
 414                         /* RFC1183 */
 415                         if ((n = getstr_str(buf2, sizeof buf2, &startp,
 416                                          endp)) < 0)
 417                                 return (-1);
 418                         if (n > 255)
 419                                 return (-1);
 420                         ShrinkBuffer(n+1);
 421                         *cp++ = n;
 422                         memcpy(cp, buf2, n);
 423                         cp += n;
 424                         break;
 425                 case T_ISDN:
 426                         /* RFC1183 */
 427                         if ((n = getstr_str(buf2, sizeof buf2, &startp,
 428                                          endp)) < 0)
 429                                 return (-1);
 430                         if ((n > 255) || (n == 0))
 431                                 return (-1);
 432                         ShrinkBuffer(n+1);
 433                         *cp++ = n;
 434                         memcpy(cp, buf2, n);
 435                         cp += n;
 436                         if ((n = getstr_str(buf2, sizeof buf2, &startp,
 437                                          endp)) < 0)
 438                                 n = 0;
 439                         if (n > 255)
 440                                 return (-1);
 441                         ShrinkBuffer(n+1);
 442                         *cp++ = n;
 443                         memcpy(cp, buf2, n);
 444                         cp += n;
 445                         break;
 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 #ifdef _LIBC
 465                         return (-1);
 466 #else
 467                     {
 468                         int sig_type, success, dateerror;
 469                         u_int32_t exptime, timesigned;
 470
 471                         /* type */
 472                         if ((n = getword_str(buf2, sizeof buf2,
 473                                              &startp, endp)) < 0)
 474                                 return (-1);
 475                         sig_type = sym_ston(__p_type_syms, buf2, &success);
 476                         if (!success || sig_type == ns_t_any)
 477                                 return (-1);
 478                         ShrinkBuffer(INT16SZ);
 479                         PUTSHORT(sig_type, cp);
 480                         /* alg */
 481                         n = getnum_str(&startp, endp);
 482                         if (n < 0)
 483                                 return (-1);
 484                         ShrinkBuffer(1);
 485                         *cp++ = n;
 486                         /* labels */
 487                         n = getnum_str(&startp, endp);
 488                         if (n <= 0 || n > 255)
 489                                 return (-1);
 490                         ShrinkBuffer(1);
 491                         *cp++ = n;
 492                         /* ottl  & expire */
 493                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 494                                 return (-1);
 495                         exptime = ns_datetosecs(buf2, &dateerror);
 496                         if (!dateerror) {
 497                                 ShrinkBuffer(INT32SZ);
 498                                 PUTLONG(rttl, cp);
 499                         }
 500                         else {
 501                                 char *ulendp;
 502                                 u_int32_t ottl;
 503
 504                                 errno = 0;
 505                                 ottl = strtoul(buf2, &ulendp, 10);
 506                                 if (errno != 0 ||
 507                                     (ulendp != NULL && *ulendp != '\0'))
 508                                         return (-1);
 509                                 ShrinkBuffer(INT32SZ);
 510                                 PUTLONG(ottl, cp);
 511                                 if (!getword_str(buf2, sizeof buf2, &startp,
 512                                                  endp))
 513                                         return (-1);
 514                                 exptime = ns_datetosecs(buf2, &dateerror);
 515                                 if (dateerror)
 516                                         return (-1);
 517                         }
 518                         /* expire */
 519                         ShrinkBuffer(INT32SZ);
 520                         PUTLONG(exptime, cp);
 521                         /* timesigned */
 522                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 523                                 return (-1);
 524                         timesigned = ns_datetosecs(buf2, &dateerror);
 525                         if (!dateerror) {
 526                                 ShrinkBuffer(INT32SZ);
 527                                 PUTLONG(timesigned, cp);
 528                         }
 529                         else
 530                                 return (-1);
 531                         /* footprint */
 532                         n = getnum_str(&startp, endp);
 533                         if (n < 0)
 534                                 return (-1);
 535                         ShrinkBuffer(INT16SZ);
 536                         PUTSHORT(n, cp);
 537                         /* signer name */
 538                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 539                                 return (-1);
 540                         n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 541                         if (n < 0)
 542                                 return (-1);
 543                         cp += n;
 544                         ShrinkBuffer(n);
 545                         /* sig */
 546                         if ((n = getword_str(buf2, sizeof buf2,
 547                                              &startp, endp)) < 0)
 548                                 return (-1);
 549                         siglen = b64_pton(buf2, buf3, sizeof(buf3));
 550                         if (siglen < 0)
 551                                 return (-1);
 552                         ShrinkBuffer(siglen);
 553                         memcpy(cp, buf3, siglen);
 554                         cp += siglen;
 555                         break;
 556                     }
 557 #endif
 558                 case ns_t_key:
 559                         /* flags */
 560                         n = gethexnum_str(&startp, endp);
 561                         if (n < 0)
 562                                 return (-1);
 563                         ShrinkBuffer(INT16SZ);
 564                         PUTSHORT(n, cp);
 565                         /* proto */
 566                         n = getnum_str(&startp, endp);
 567                         if (n < 0)
 568                                 return (-1);
 569                         ShrinkBuffer(1);
 570                         *cp++ = n;
 571                         /* alg */
 572                         n = getnum_str(&startp, endp);
 573                         if (n < 0)
 574                                 return (-1);
 575                         ShrinkBuffer(1);
 576                         *cp++ = n;
 577                         /* key */
 578                         if ((n = getword_str(buf2, sizeof buf2,
 579                                              &startp, endp)) < 0)
 580                                 return (-1);
 581                         keylen = b64_pton(buf2, buf3, sizeof(buf3));
 582                         if (keylen < 0)
 583                                 return (-1);
 584                         ShrinkBuffer(keylen);
 585                         memcpy(cp, buf3, keylen);
 586                         cp += keylen;
 587                         break;
 588                 case ns_t_nxt:
 589                     {
 590                         int success, nxt_type;
 591                         u_char data[32];
 592                         int maxtype;
 593
 594                         /* next name */
 595                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 596                                 return (-1);
 597                         n = dn_comp(buf2, cp, buflen, NULL, NULL);
 598                         if (n < 0)
 599                                 return (-1);
 600                         cp += n;
 601                         ShrinkBuffer(n);
 602                         maxtype = 0;
 603                         memset(data, 0, sizeof data);
 604                         for (;;) {
 605                                 if (!getword_str(buf2, sizeof buf2, &startp,
 606                                                  endp))
 607                                         break;
 608                                 nxt_type = sym_ston(__p_type_syms, buf2,
 609                                                     &success);
 610                                 if (!success || !ns_t_rr_p(nxt_type))
 611                                         return (-1);
 612                                 NS_NXT_BIT_SET(nxt_type, data);
 613                                 if (nxt_type > maxtype)
 614                                         maxtype = nxt_type;
 615                         }
 616                         n = maxtype/NS_NXT_BITS+1;
 617                         ShrinkBuffer(n);
 618                         memcpy(cp, data, n);
 619                         cp += n;
 620                         break;
 621                     }
 622                 case ns_t_cert:
 623                         /* type */
 624                         n = getnum_str(&startp, endp);
 625                         if (n < 0)
 626                                 return (-1);
 627                         ShrinkBuffer(INT16SZ);
 628                         PUTSHORT(n, cp);
 629                         /* key tag */
 630                         n = getnum_str(&startp, endp);
 631                         if (n < 0)
 632                                 return (-1);
 633                         ShrinkBuffer(INT16SZ);
 634                         PUTSHORT(n, cp);
 635                         /* alg */
 636                         n = getnum_str(&startp, endp);
 637                         if (n < 0)
 638                                 return (-1);
 639                         ShrinkBuffer(1);
 640                         *cp++ = n;
 641                         /* cert */
 642                         if ((n = getword_str(buf2, sizeof buf2,
 643                                              &startp, endp)) < 0)
 644                                 return (-1);
 645                         certlen = b64_pton(buf2, buf3, sizeof(buf3));
 646                         if (certlen < 0)
 647                                 return (-1);
 648                         ShrinkBuffer(certlen);
 649                         memcpy(cp, buf3, certlen);
 650                         cp += certlen;
 651                         break;
 652                 case ns_t_aaaa:
 653                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 654                                 return (-1);
 655                         if (inet_pton(AF_INET6, buf2, &in6a) <= 0)
 656                                 return (-1);
 657                         ShrinkBuffer(NS_IN6ADDRSZ);
 658                         memcpy(cp, &in6a, NS_IN6ADDRSZ);
 659                         cp += NS_IN6ADDRSZ;
 660                         break;
 661                 case ns_t_naptr:
 662                         /* Order Preference Flags Service Replacement Regexp */
 663                         /* Order */
 664                         n = getnum_str(&startp, endp);
 665                         if (n < 0 || n > 65535)
 666                                 return (-1);
 667                         ShrinkBuffer(INT16SZ);
 668                         PUTSHORT(n, cp);
 669                         /* Preference */
 670                         n = getnum_str(&startp, endp);
 671                         if (n < 0 || n > 65535)
 672                                 return (-1);
 673                         ShrinkBuffer(INT16SZ);
 674                         PUTSHORT(n, cp);
 675                         /* Flags */
 676                         if ((n = getstr_str(buf2, sizeof buf2,
 677                                         &startp, endp)) < 0) {
 678                                 return (-1);
 679                         }
 680                         if (n > 255)
 681                                 return (-1);
 682                         ShrinkBuffer(n+1);
 683                         *cp++ = n;
 684                         memcpy(cp, buf2, n);
 685                         cp += n;
 686                         /* Service Classes */
 687                         if ((n = getstr_str(buf2, sizeof buf2,
 688                                         &startp, endp)) < 0) {
 689                                 return (-1);
 690                         }
 691                         if (n > 255)
 692                                 return (-1);
 693                         ShrinkBuffer(n+1);
 694                         *cp++ = n;
 695                         memcpy(cp, buf2, n);
 696                         cp += n;
 697                         /* Pattern */
 698                         if ((n = getstr_str(buf2, sizeof buf2,
 699                                         &startp, endp)) < 0) {
 700                                 return (-1);
 701                         }
 702                         if (n > 255)
 703                                 return (-1);
 704                         ShrinkBuffer(n+1);
 705                         *cp++ = n;
 706                         memcpy(cp, buf2, n);
 707                         cp += n;
 708                         /* Replacement */
 709                         if (!getword_str(buf2, sizeof buf2, &startp, endp))
 710                                 return (-1);
 711                         n = dn_comp(buf2, cp, buflen, NULL, NULL);
 712                         if (n < 0)
 713                                 return (-1);
 714                         cp += n;
 715                         ShrinkBuffer(n);
 716                         break;
 717                 default:
 718                         return (-1);
 719                 } /*switch*/
 720                 n = (u_int16_t)((cp - sp2) - INT16SZ);
 721                 PUTSHORT(n, sp2);
 722         } /*for*/
 723
 724         hp->qdcount = htons(counts[0]);
 725         hp->ancount = htons(counts[1]);
 726         hp->nscount = htons(counts[2]);
 727         hp->arcount = htons(counts[3]);
 728         return (cp - buf);
 729 }
 730
 731 /*%
 732  * Get a whitespace delimited word from a string (not file)
 733  * into buf. modify the start pointer to point after the
 734  * word in the string.
 735  */
 736 static int
 737 getword_str(char *buf, int size, u_char **startpp, u_char *endp) {
 738         char *cp;
 739         int c;
 740
 741         for (cp = buf; *startpp <= endp; ) {
 742                 c = **startpp;
 743                 if (isspace(c) || c == '\0') {
 744                         if (cp != buf) /*%< trailing whitespace */
 745                                 break;
 746                         else { /*%< leading whitespace */
 747                                 (*startpp)++;
 748                                 continue;
 749                         }
 750                 }
 751                 (*startpp)++;
 752                 if (cp >= buf+size-1)
 753                         break;
 754                 *cp++ = (u_char)c;
 755         }
 756         *cp = '\0';
 757         return (cp != buf);
 758 }
 759
 760 /*%
 761  * get a white spae delimited string from memory.  Process quoted strings
 762  * and \\DDD escapes.  Return length or -1 on error.  Returned string may
 763  * contain nulls.
 764  */
 765 static char digits[] = "0123456789";
 766 static int
 767 getstr_str(char *buf, int size, u_char **startpp, u_char *endp) {
 768         char *cp;
 769         int c, c1 = 0;
 770         int inquote = 0;
 771         int seen_quote = 0;
 772         int escape = 0;
 773         int dig = 0;
 774
 775         for (cp = buf; *startpp <= endp; ) {
 776                 if ((c = **startpp) == '\0')
 777                         break;
 778                 /* leading white space */
 779                 if ((cp == buf) && !seen_quote && isspace(c)) {
 780                         (*startpp)++;
 781                         continue;
 782                 }
 783
 784                 switch (c) {
 785                 case '\\':
 786                         if (!escape)  {
 787                                 escape = 1;
 788                                 dig = 0;
 789                                 c1 = 0;
 790                                 (*startpp)++;
 791                                 continue;
 792                         }
 793                         goto do_escape;
 794                 case '"':
 795                         if (!escape) {
 796                                 inquote = !inquote;
 797                                 seen_quote = 1;
 798                                 (*startpp)++;
 799                                 continue;
 800                         }
 801                         /* fall through */
 802                 default:
 803                 do_escape:
 804                         if (escape) {
 805                                 switch (c) {
 806                                 case '0':
 807                                 case '1':
 808                                 case '2':
 809                                 case '3':
 810                                 case '4':
 811                                 case '5':
 812                                 case '6':
 813                                 case '7':
 814                                 case '8':
 815                                 case '9':
 816                                         c1 = c1 * 10 +
 817                                                 (strchr(digits, c) - digits);
 818
 819                                         if (++dig == 3) {
 820                                                 c = c1 &0xff;
 821                                                 break;
 822                                         }
 823                                         (*startpp)++;
 824                                         continue;
 825                                 }
 826                                 escape = 0;
 827                         } else if (!inquote && isspace(c))
 828                                 goto done;
 829                         if (cp >= buf+size-1)
 830                                 goto done;
 831                         *cp++ = (u_char)c;
 832                         (*startpp)++;
 833                 }
 834         }
 835  done:
 836         *cp = '\0';
 837         return ((cp == buf)?  (seen_quote? 0: -1): (cp - buf));
 838 }
 839
 840 /*%
 841  * Get a whitespace delimited base 16 number from a string (not file) into buf
 842  * update the start pointer to point after the number in the string.
 843  */
 844 static int
 845 gethexnum_str(u_char **startpp, u_char *endp) {
 846         int c, n;
 847         int seendigit = 0;
 848         int m = 0;
 849
 850         if (*startpp + 2 >= endp || strncasecmp((char *)*startpp, "0x", 2) != 0)
 851                 return getnum_str(startpp, endp);
 852         (*startpp)+=2;
 853         for (n = 0; *startpp <= endp; ) {
 854                 c = **startpp;
 855                 if (isspace(c) || c == '\0') {
 856                         if (seendigit) /*%< trailing whitespace */
 857                                 break;
 858                         else { /*%< leading whitespace */
 859                                 (*startpp)++;
 860                                 continue;
 861                         }
 862                 }
 863                 if (c == ';') {
 864                         while ((*startpp <= endp) &&
 865                                ((c = **startpp) != '\n'))
 866                                         (*startpp)++;
 867                         if (seendigit)
 868                                 break;
 869                         continue;
 870                 }
 871                 if (!isxdigit(c)) {
 872                         if (c == ')' && seendigit) {
 873                                 (*startpp)--;
 874                                 break;
 875                         }
 876                         return (-1);
 877                 }
 878                 (*startpp)++;
 879                 if (isdigit(c))
 880                         n = n * 16 + (c - '0');
 881                 else
 882                         n = n * 16 + (tolower(c) - 'a' + 10);
 883                 seendigit = 1;
 884         }
 885         return (n + m);
 886 }
 887
 888 /*%
 889  * Get a whitespace delimited base 10 number from a string (not file) into buf
 890  * update the start pointer to point after the number in the string.
 891  */
 892 static int
 893 getnum_str(u_char **startpp, u_char *endp) {
 894         int c, n;
 895         int seendigit = 0;
 896         int m = 0;
 897
 898         for (n = 0; *startpp <= endp; ) {
 899                 c = **startpp;
 900                 if (isspace(c) || c == '\0') {
 901                         if (seendigit) /*%< trailing whitespace */
 902                                 break;
 903                         else { /*%< leading whitespace */
 904                                 (*startpp)++;
 905                                 continue;
 906                         }
 907                 }
 908                 if (c == ';') {
 909                         while ((*startpp <= endp) &&
 910                                ((c = **startpp) != '\n'))
 911                                         (*startpp)++;
 912                         if (seendigit)
 913                                 break;
 914                         continue;
 915                 }
 916                 if (!isdigit(c)) {
 917                         if (c == ')' && seendigit) {
 918                                 (*startpp)--;
 919                                 break;
 920                         }
 921                         return (-1);
 922                 }
 923                 (*startpp)++;
 924                 n = n * 10 + (c - '0');
 925                 seendigit = 1;
 926         }
 927         return (n + m);
 928 }
 929
 930 /*%
 931  * Allocate a resource record buffer & save rr info.
 932  */
 933 ns_updrec *
 934 res_mkupdrec(int section, const char *dname,
 935              u_int class, u_int type, u_long ttl) {
 936         ns_updrec *rrecp = (ns_updrec *)calloc(1, sizeof(ns_updrec));
 937
 938         if (!rrecp || !(rrecp->r_dname = strdup(dname))) {
 939                 if (rrecp)
 940                         free((char *)rrecp);
 941                 return (NULL);
 942         }
 943         INIT_LINK(rrecp, r_link);
 944         INIT_LINK(rrecp, r_glink);
 945         rrecp->r_class = (ns_class)class;
 946         rrecp->r_type = (ns_type)type;
 947         rrecp->r_ttl = ttl;
 948         rrecp->r_section = (ns_sect)section;
 949         return (rrecp);
 950 }
 951
 952 /*%
 953  * Free a resource record buffer created by res_mkupdrec.
 954  */
 955 void
 956 res_freeupdrec(ns_updrec *rrecp) {
 957         /* Note: freeing r_dp is the caller's responsibility. */
 958         if (rrecp->r_dname != NULL)
 959                 free(rrecp->r_dname);
 960         free(rrecp);
 961 }
 962
 963 struct valuelist {
 964         struct valuelist *      next;
 965         struct valuelist *      prev;
 966         char *                  name;
 967         char *                  proto;
 968         int                     port;
 969 };
 970 static struct valuelist *servicelist, *protolist;
 971
 972 static void
 973 res_buildservicelist(void) {
 974         struct servent *sp;
 975         struct valuelist *slp;
 976
 977 #ifdef MAYBE_HESIOD
 978         setservent(0);
 979 #else
 980         setservent(1);
 981 #endif
 982         while ((sp = getservent()) != NULL) {
 983                 slp = (struct valuelist *)malloc(sizeof(struct valuelist));
 984                 if (!slp)
 985                         break;
 986                 slp->name = strdup(sp->s_name);
 987                 slp->proto = strdup(sp->s_proto);
 988                 if ((slp->name == NULL) || (slp->proto == NULL)) {
 989                         if (slp->name) free(slp->name);
 990                         if (slp->proto) free(slp->proto);
 991                         free(slp);
 992                         break;
 993                 }
 994                 slp->port = ntohs((u_int16_t)sp->s_port);  /*%< host byt order */
 995                 slp->next = servicelist;
 996                 slp->prev = NULL;
 997                 if (servicelist)
 998                         servicelist->prev = slp;
 999                 servicelist = slp;
1000         }
1001         endservent();
1002 }
1003
1004 #ifndef _LIBC
1005 void
1006 res_destroyservicelist() {
1007         struct valuelist *slp, *slp_next;
1008
1009         for (slp = servicelist; slp != NULL; slp = slp_next) {
1010                 slp_next = slp->next;
1011                 free(slp->name);
1012                 free(slp->proto);
1013                 free(slp);
1014         }
1015         servicelist = (struct valuelist *)0;
1016 }
1017 #endif
1018
1019 #ifdef _LIBC
1020 static
1021 #endif
1022 void
1023 res_buildprotolist(void) {
1024         struct protoent *pp;
1025         struct valuelist *slp;
1026
1027 #ifdef MAYBE_HESIOD
1028         setprotoent(0);
1029 #else
1030         setprotoent(1);
1031 #endif
1032         while ((pp = getprotoent()) != NULL) {
1033                 slp = (struct valuelist *)malloc(sizeof(struct valuelist));
1034                 if (!slp)
1035                         break;
1036                 slp->name = strdup(pp->p_name);
1037                 if (slp->name == NULL) {
1038                         free(slp);
1039                         break;
1040                 }
1041                 slp->port = pp->p_proto;        /*%< host byte order */
1042                 slp->next = protolist;
1043                 slp->prev = NULL;
1044                 if (protolist)
1045                         protolist->prev = slp;
1046                 protolist = slp;
1047         }
1048         endprotoent();
1049 }
1050
1051 #ifndef _LIBC
1052 void
1053 res_destroyprotolist(void) {
1054         struct valuelist *plp, *plp_next;
1055
1056         for (plp = protolist; plp != NULL; plp = plp_next) {
1057                 plp_next = plp->next;
1058                 free(plp->name);
1059                 free(plp);
1060         }
1061         protolist = (struct valuelist *)0;
1062 }
1063 #endif
1064
1065 static int
1066 findservice(const char *s, struct valuelist **list) {
1067         struct valuelist *lp = *list;
1068         int n;
1069
1070         for (; lp != NULL; lp = lp->next)
1071                 if (strcasecmp(lp->name, s) == 0) {
1072                         if (lp != *list) {
1073                                 lp->prev->next = lp->next;
1074                                 if (lp->next)
1075                                         lp->next->prev = lp->prev;
1076                                 (*list)->prev = lp;
1077                                 lp->next = *list;
1078                                 *list = lp;
1079                         }
1080                         return (lp->port);      /*%< host byte order */
1081                 }
1082         if (sscanf(s, "%d", &n) != 1 || n <= 0)
1083                 n = -1;
1084         return (n);
1085 }
1086
1087 /*%
1088  * Convert service name or (ascii) number to int.
1089  */
1090 #ifdef _LIBC
1091 static
1092 #endif
1093 int
1094 res_servicenumber(const char *p) {
1095         if (servicelist == (struct valuelist *)0)
1096                 res_buildservicelist();
1097         return (findservice(p, &servicelist));
1098 }
1099
1100 /*%
1101  * Convert protocol name or (ascii) number to int.
1102  */
1103 #ifdef _LIBC
1104 static
1105 #endif
1106 int
1107 res_protocolnumber(const char *p) {
1108         if (protolist == (struct valuelist *)0)
1109                 res_buildprotolist();
1110         return (findservice(p, &protolist));
1111 }
1112
1113 #ifndef _LIBC
1114 static struct servent *
1115 cgetservbyport(u_int16_t port, const char *proto) {     /*%< Host byte order. */
1116         struct valuelist **list = &servicelist;
1117         struct valuelist *lp = *list;
1118         static struct servent serv;
1119
1120         port = ntohs(port);
1121         for (; lp != NULL; lp = lp->next) {
1122                 if (port != (u_int16_t)lp->port)        /*%< Host byte order. */
1123                         continue;
1124                 if (strcasecmp(lp->proto, proto) == 0) {
1125                         if (lp != *list) {
1126                                 lp->prev->next = lp->next;
1127                                 if (lp->next)
1128                                         lp->next->prev = lp->prev;
1129                                 (*list)->prev = lp;
1130                                 lp->next = *list;
1131                                 *list = lp;
1132                         }
1133                         serv.s_name = lp->name;
1134                         serv.s_port = htons((u_int16_t)lp->port);
1135                         serv.s_proto = lp->proto;
1136                         return (&serv);
1137                 }
1138         }
1139         return (0);
1140 }
1141
1142 static struct protoent *
1143 cgetprotobynumber(int proto) {                          /*%< Host byte order. */
1144         struct valuelist **list = &protolist;
1145         struct valuelist *lp = *list;
1146         static struct protoent prot;
1147
1148         for (; lp != NULL; lp = lp->next)
1149                 if (lp->port == proto) {                /*%< Host byte order. */
1150                         if (lp != *list) {
1151                                 lp->prev->next = lp->next;
1152                                 if (lp->next)
1153                                         lp->next->prev = lp->prev;
1154                                 (*list)->prev = lp;
1155                                 lp->next = *list;
1156                                 *list = lp;
1157                         }
1158                         prot.p_name = lp->name;
1159                         prot.p_proto = lp->port;        /*%< Host byte order. */
1160                         return (&prot);
1161                 }
1162         return (0);
1163 }
1164
1165 const char *
1166 res_protocolname(int num) {
1167         static char number[8];
1168         struct protoent *pp;
1169
1170         if (protolist == (struct valuelist *)0)
1171                 res_buildprotolist();
1172         pp = cgetprotobynumber(num);
1173         if (pp == NULL)  {
1174                 (void) sprintf(number, "%d", num);
1175                 return (number);
1176         }
1177         return (pp->p_name);
1178 }
1179
1180 const char *
1181 res_servicename(u_int16_t port, const char *proto) {    /*%< Host byte order. */
1182         static char number[8];
1183         struct servent *ss;
1184
1185         if (servicelist == (struct valuelist *)0)
1186                 res_buildservicelist();
1187         ss = cgetservbyport(htons(port), proto);
1188         if (ss == NULL)  {
1189                 (void) sprintf(number, "%d", port);
1190                 return (number);
1191         }
1192         return (ss->s_name);
1193 }
1194 #endif