StdLib/BsdSocketLib/res_mkupdate.c

   1 /*
   2  * Copyright (c) 1996 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  * Portions copyright (c) 1999, 2000
  20  * Intel Corporation.
  21  * All rights reserved.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  *
  27  * 1. Redistributions of source code must retain the above copyright
  28  *    notice, this list of conditions and the following disclaimer.
  29  *
  30  * 2. Redistributions in binary form must reproduce the above copyright
  31  *    notice, this list of conditions and the following disclaimer in the
  32  *    documentation and/or other materials provided with the distribution.
  33  *
  34  * 3. All advertising materials mentioning features or use of this software
  35  *    must display the following acknowledgement:
  36  *
  37  *    This product includes software developed by Intel Corporation and
  38  *    its contributors.
  39  *
  40  * 4. Neither the name of Intel Corporation or its contributors may be
  41  *    used to endorse or promote products derived from this software
  42  *    without specific prior written permission.
  43  *
  44  * THIS SOFTWARE IS PROVIDED BY INTEL CORPORATION AND CONTRIBUTORS ``AS IS''
  45  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  47  * ARE DISCLAIMED.  IN NO EVENT SHALL INTEL CORPORATION OR CONTRIBUTORS BE
  48  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  49  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  50  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  51  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  52  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  53  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  54  * THE POSSIBILITY OF SUCH DAMAGE.
  55  *
  56  */
  57
  58 /*
  59  * Based on the Dynamic DNS reference implementation by Viraj Bais
  60  * <viraj_bais@ccm.fm.intel.com>
  61  */
  62
  63 #if !defined(lint) && !defined(SABER)
  64 static char rcsid[] = "$Id: res_mkupdate.c,v 1.1.1.1 2003/11/19 01:51:38 kyu3 Exp $";
  65 #endif /* not lint */
  66
  67 #include <sys/types.h>
  68 #include <sys/param.h>
  69
  70 #include <netinet/in.h>
  71 #include <arpa/nameser.h>
  72 #include <arpa/inet.h>
  73
  74 #include <errno.h>
  75 #include <limits.h>
  76 #include <netdb.h>
  77 #include <resolv.h>
  78 #include <stdio.h>
  79 #include <stdlib.h>
  80 #include <string.h>
  81 #include <unistd.h>
  82 #include <ctype.h>
  83
  84 #include "res_config.h"
  85
  86 static int getnum_str(u_char **, u_char *);
  87 static int getword_str(char *, int, u_char **, u_char *);
  88
  89 #define ShrinkBuffer(x)  if ((buflen -= x) < 0) return (-2);
  90
  91 /*
  92  * Form update packets.
  93  * Returns the size of the resulting packet if no error
  94  * On error,
  95  *  returns -1 if error in reading a word/number in rdata
  96  *         portion for update packets
  97  *      -2 if length of buffer passed is insufficient
  98  *      -3 if zone section is not the first section in
  99  *         the linked list, or section order has a problem
 100  *      -4 on a number overflow
 101  *      -5 unknown operation or no records
 102  */
 103 int
 104 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
 105     ns_updrec *rrecp_start = rrecp_in;
 106     HEADER *hp;
 107     u_char *cp, *sp1, *sp2, *startp, *endp;
 108     int n, i, soanum, multiline;
 109     ns_updrec *rrecp;
 110     struct in_addr ina;
 111         char buf2[MAXDNAME];
 112     int section, numrrs = 0, counts[ns_s_max];
 113     u_int16_t rtype, rclass;
 114     u_int32_t n1, rttl;
 115     u_char *dnptrs[20], **dpp, **lastdnptr;
 116
 117     if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
 118         h_errno = NETDB_INTERNAL;
 119         return (-1);
 120     }
 121
 122     /*
 123      * Initialize header fields.
 124      */
 125     if ((buf == NULL) || (buflen < HFIXEDSZ))
 126         return (-1);
 127     memset(buf, 0, HFIXEDSZ);
 128     hp = (HEADER *) buf;
 129     hp->id = htons(++_res.id);
 130     hp->opcode = ns_o_update;
 131     hp->rcode = NOERROR;
 132     sp1 = buf + 2*INT16SZ;  /* save pointer to zocount */
 133     cp = buf + HFIXEDSZ;
 134     buflen -= HFIXEDSZ;
 135     dpp = dnptrs;
 136     *dpp++ = buf;
 137     *dpp++ = NULL;
 138     lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
 139
 140     if (rrecp_start == NULL)
 141         return (-5);
 142     else if (rrecp_start->r_section != S_ZONE)
 143         return (-3);
 144
 145     memset(counts, 0, sizeof counts);
 146     for (rrecp = rrecp_start; rrecp; rrecp = rrecp->r_grpnext) {
 147         numrrs++;
 148                 section = rrecp->r_section;
 149         if (section < 0 || section >= ns_s_max)
 150             return (-1);
 151         counts[section]++;
 152         for (i = section + 1; i < ns_s_max; i++)
 153             if (counts[i])
 154                 return (-3);
 155         rtype = rrecp->r_type;
 156         rclass = rrecp->r_class;
 157         rttl = rrecp->r_ttl;
 158         /* overload class and type */
 159         if (section == S_PREREQ) {
 160             rttl = 0;
 161             switch (rrecp->r_opcode) {
 162             case YXDOMAIN:
 163                 rclass = C_ANY;
 164                 rtype = T_ANY;
 165                 rrecp->r_size = 0;
 166                 break;
 167             case NXDOMAIN:
 168                 rclass = C_NONE;
 169                 rtype = T_ANY;
 170                 rrecp->r_size = 0;
 171                 break;
 172             case NXRRSET:
 173                 rclass = C_NONE;
 174                 rrecp->r_size = 0;
 175                 break;
 176             case YXRRSET:
 177                 if (rrecp->r_size == 0)
 178                     rclass = C_ANY;
 179                 break;
 180             default:
 181                 fprintf(stderr,
 182                     "res_mkupdate: incorrect opcode: %d\n",
 183                     rrecp->r_opcode);
 184                 fflush(stderr);
 185                 return (-1);
 186             }
 187         } else if (section == S_UPDATE) {
 188             switch (rrecp->r_opcode) {
 189             case DELETE:
 190                 rclass = rrecp->r_size == 0 ? C_ANY : C_NONE;
 191                 break;
 192             case ADD:
 193                 break;
 194             default:
 195                 fprintf(stderr,
 196                     "res_mkupdate: incorrect opcode: %d\n",
 197                     rrecp->r_opcode);
 198                 fflush(stderr);
 199                 return (-1);
 200             }
 201         }
 202
 203         /*
 204          * XXX  appending default domain to owner name is omitted,
 205          *  fqdn must be provided
 206          */
 207         if ((n = dn_comp(rrecp->r_dname, cp, buflen, dnptrs,
 208                  lastdnptr)) < 0)
 209             return (-1);
 210         cp += n;
 211         ShrinkBuffer(n + 2*INT16SZ);
 212         PUTSHORT(rtype, cp);
 213         PUTSHORT(rclass, cp);
 214         if (section == S_ZONE) {
 215             if (numrrs != 1 || rrecp->r_type != T_SOA)
 216                 return (-3);
 217             continue;
 218         }
 219         ShrinkBuffer(INT32SZ + INT16SZ);
 220         PUTLONG(rttl, cp);
 221         sp2 = cp;  /* save pointer to length byte */
 222         cp += INT16SZ;
 223         if (rrecp->r_size == 0) {
 224             if (section == S_UPDATE && rclass != C_ANY)
 225                 return (-1);
 226             else {
 227                 PUTSHORT(0, sp2);
 228                 continue;
 229             }
 230         }
 231         startp = rrecp->r_data;
 232         endp = startp + rrecp->r_size - 1;
 233         /* XXX this should be done centrally. */
 234         switch (rrecp->r_type) {
 235         case T_A:
 236             if (!getword_str(buf2, sizeof buf2, &startp, endp))
 237                 return (-1);
 238             if (!inet_aton(buf2, &ina))
 239                 return (-1);
 240             n1 = ntohl(ina.s_addr);
 241             ShrinkBuffer(INT32SZ);
 242             PUTLONG(n1, cp);
 243             break;
 244         case T_CNAME:
 245         case T_MB:
 246         case T_MG:
 247         case T_MR:
 248         case T_NS:
 249         case T_PTR:
 250             if (!getword_str(buf2, sizeof buf2, &startp, endp))
 251                 return (-1);
 252             n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 253             if (n < 0)
 254                 return (-1);
 255             cp += n;
 256             ShrinkBuffer(n);
 257             break;
 258         case T_MINFO:
 259         case T_SOA:
 260         case T_RP:
 261             for (i = 0; i < 2; i++) {
 262                 if (!getword_str(buf2, sizeof buf2, &startp,
 263                          endp))
 264                 return (-1);
 265                 n = dn_comp(buf2, cp, buflen,
 266                         dnptrs, lastdnptr);
 267                 if (n < 0)
 268                     return (-1);
 269                 cp += n;
 270                 ShrinkBuffer(n);
 271             }
 272             if (rrecp->r_type == T_SOA) {
 273                 ShrinkBuffer(5 * INT32SZ);
 274                 while (isspace(*startp) || !*startp)
 275                     startp++;
 276                 if (*startp == '(') {
 277                     multiline = 1;
 278                     startp++;
 279                 } else
 280                     multiline = 0;
 281                 /* serial, refresh, retry, expire, minimum */
 282                 for (i = 0; i < 5; i++) {
 283                     soanum = getnum_str(&startp, endp);
 284                     if (soanum < 0)
 285                         return (-1);
 286                     PUTLONG(soanum, cp);
 287                 }
 288                 if (multiline) {
 289                     while (isspace(*startp) || !*startp)
 290                         startp++;
 291                     if (*startp != ')')
 292                         return (-1);
 293                 }
 294             }
 295             break;
 296         case T_MX:
 297         case T_AFSDB:
 298         case T_RT:
 299             n = getnum_str(&startp, endp);
 300             if (n < 0)
 301                 return (-1);
 302             PUTSHORT(n, cp);
 303             ShrinkBuffer(INT16SZ);
 304             if (!getword_str(buf2, sizeof buf2, &startp, endp))
 305                 return (-1);
 306             n = dn_comp(buf2, cp, buflen, dnptrs, lastdnptr);
 307             if (n < 0)
 308                 return (-1);
 309             cp += n;
 310             ShrinkBuffer(n);
 311             break;
 312         case T_PX:
 313             n = getnum_str(&startp, endp);
 314             if (n < 0)
 315                 return (-1);
 316             PUTSHORT(n, cp);
 317             ShrinkBuffer(INT16SZ);
 318             for (i = 0; i < 2; i++) {
 319                 if (!getword_str(buf2, sizeof buf2, &startp,
 320                          endp))
 321                     return (-1);
 322                 n = dn_comp(buf2, cp, buflen, dnptrs,
 323                         lastdnptr);
 324                 if (n < 0)
 325                     return (-1);
 326                 cp += n;
 327                 ShrinkBuffer(n);
 328             }
 329             break;
 330         case T_WKS:
 331         case T_HINFO:
 332         case T_TXT:
 333         case T_X25:
 334         case T_ISDN:
 335         case T_NSAP:
 336         case T_LOC:
 337             /* XXX - more fine tuning needed here */
 338             ShrinkBuffer(rrecp->r_size);
 339             memcpy(cp, rrecp->r_data, rrecp->r_size);
 340             cp += rrecp->r_size;
 341             break;
 342         default:
 343             return (-1);
 344         } /*switch*/
 345         n = (u_int16_t)((cp - sp2) - INT16SZ);
 346         PUTSHORT(n, sp2);
 347     } /*for*/
 348
 349     hp->qdcount = htons(counts[0]);
 350     hp->ancount = htons(counts[1]);
 351     hp->nscount = htons(counts[2]);
 352     hp->arcount = htons(counts[3]);
 353     return ((int)(cp - buf));
 354 }
 355
 356 /*
 357  * Get a whitespace delimited word from a string (not file)
 358  * into buf. modify the start pointer to point after the
 359  * word in the string.
 360  */
 361 static int
 362 getword_str(char *buf, int size, u_char **startpp, u_char *endp) {
 363         char *cp;
 364         int c;
 365
 366         for (cp = buf; *startpp <= endp; ) {
 367                 c = **startpp;
 368                 if (isspace(c) || c == '\0') {
 369                         if (cp != buf) /* trailing whitespace */
 370                                 break;
 371                         else { /* leading whitespace */
 372                                 (*startpp)++;
 373                                 continue;
 374                         }
 375                 }
 376                 (*startpp)++;
 377                 if (cp >= buf+size-1)
 378                         break;
 379                 *cp++ = (u_char)c;
 380         }
 381         *cp = '\0';
 382         return (cp != buf);
 383 }
 384
 385 /*
 386  * Get a whitespace delimited number from a string (not file) into buf
 387  * update the start pointer to point after the number in the string.
 388  */
 389 static int
 390 getnum_str(u_char **startpp, u_char *endp) {
 391         int c;
 392         int n;
 393         int seendigit = 0;
 394         int m = 0;
 395
 396         for (n = 0; *startpp <= endp; ) {
 397                 c = **startpp;
 398                 if (isspace(c) || c == '\0') {
 399                         if (seendigit) /* trailing whitespace */
 400                                 break;
 401                         else { /* leading whitespace */
 402                                 (*startpp)++;
 403                                 continue;
 404                         }
 405                 }
 406                 if (c == ';') {
 407                         while ((*startpp <= endp) &&
 408                    ((c = **startpp) != '\n'))
 409                     (*startpp)++;
 410                         if (seendigit)
 411                                 break;
 412                         continue;
 413                 }
 414                 if (!isdigit(c)) {
 415                         if (c == ')' && seendigit) {
 416                                 (*startpp)--;
 417                                 break;
 418                         }
 419             return (-1);
 420                 }
 421                 (*startpp)++;
 422                 n = n * 10 + (c - '0');
 423                 seendigit = 1;
 424         }
 425         return (n + m);
 426 }
 427
 428 /*
 429  * Allocate a resource record buffer & save rr info.
 430  */
 431 ns_updrec *
 432 res_mkupdrec(int section, const char *dname,
 433          u_int class, u_int type, u_long ttl) {
 434     ns_updrec *rrecp = (ns_updrec *)calloc(1, sizeof(ns_updrec));
 435
 436     if (!rrecp || !(rrecp->r_dname = strdup(dname)))
 437         return (NULL);
 438     rrecp->r_class = (u_int16_t)class;
 439     rrecp->r_type = (u_int16_t)type;
 440     rrecp->r_ttl = (u_int32_t)ttl;
 441     rrecp->r_section = (u_int8_t)section;
 442     return (rrecp);
 443 }
 444
 445 /*
 446  * Free a resource record buffer created by res_mkupdrec.
 447  */
 448 void
 449 res_freeupdrec(ns_updrec *rrecp) {
 450     /* Note: freeing r_dp is the caller's responsibility. */
 451     if (rrecp->r_dname != NULL)
 452         free(rrecp->r_dname);
 453     free(rrecp);
 454 }