res_mkquery.c

   1 /*
   2  * Copyright (c) 1985, 1993
   3  *    The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  36  *
  37  * Permission to use, copy, modify, and distribute this software for any
  38  * purpose with or without fee is hereby granted, provided that the above
  39  * copyright notice and this permission notice appear in all copies, and that
  40  * the name of Digital Equipment Corporation not be used in advertising or
  41  * publicity pertaining to distribution of the document or software without
  42  * specific, written prior permission.
  43  *
  44  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  45  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  46  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  47  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  48  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  49  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  50  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  51  * SOFTWARE.
  52  */
  53
  54 /*
  55  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
  56  *
  57  * Permission to use, copy, modify, and distribute this software for any
  58  * purpose with or without fee is hereby granted, provided that the above
  59  * copyright notice and this permission notice appear in all copies.
  60  *
  61  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
  62  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  63  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  64  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  65  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  66  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  67  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  68  * SOFTWARE.
  69  */
  70
  71 #if defined(LIBC_SCCS) && !defined(lint)
  72 static const char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93";
  73 static const char rcsid[] = "$Id: res_mkquery.c,v 1.1 2006/03/01 19:01:38 majka Exp $";
  74 #endif /* LIBC_SCCS and not lint */
  75
  76 #ifndef __APPLE__
  77 #include "port_before.h"
  78 #endif
  79 #include <sys/types.h>
  80 #include <sys/param.h>
  81 #include <netinet/in.h>
  82 #include <arpa/nameser.h>
  83 #include <netdb.h>
  84 #include <resolv.h>
  85 #include <stdio.h>
  86 #include <string.h>
  87 #include "res_private.h"
  88 #ifndef __APPLE__
  89 #include "port_after.h"
  90 #endif
  91
  92 /* Options.  Leave them on. */
  93 #define DEBUG
  94
  95 extern const char *__res_opcodes[];
  96
  97 /*
  98  * Form all types of queries.
  99  * Returns the size of the result or -1.
 100  */
 101 int
 102 res_nmkquery(res_state statp,
 103              int op,                    /* opcode of query */
 104              const char *dname,         /* domain name */
 105              int class, int type,       /* class and type of query */
 106              const u_char *data,        /* resource record data */
 107              int datalen,               /* length of data */
 108              const u_char *newrr_in,    /* new rr for modify or append */
 109              u_char *buf,               /* buffer to put query */
 110              int buflen)                /* size of buffer */
 111 {
 112         register HEADER *hp;
 113         register u_char *cp;
 114         register int n;
 115         u_char *dnptrs[20], **dpp, **lastdnptr;
 116
 117 #ifdef __APPLE__
 118         n = 0;
 119 #else
 120         UNUSED(newrr_in);
 121 #endif
 122
 123 #ifdef DEBUG
 124         if (statp->options & RES_DEBUG)
 125                 printf(";; res_nmkquery(%s, %s, %s, %s)\n",
 126                        __res_opcodes[op], dname, p_class(class), p_type(type));
 127 #endif
 128         /*
 129          * Initialize header fields.
 130          */
 131         if ((buf == NULL) || (buflen < NS_HFIXEDSZ))
 132                 return (-1);
 133         memset(buf, 0, NS_HFIXEDSZ);
 134         hp = (HEADER *) buf;
 135 #ifdef __APPLE__
 136         hp->id = res_randomid();
 137 #else
 138         hp->id = htons(++statp->id);
 139 #endif
 140         hp->opcode = op;
 141         hp->rd = (statp->options & RES_RECURSE) != 0;
 142         hp->rcode = ns_r_noerror;
 143         cp = buf + NS_HFIXEDSZ;
 144         buflen -= NS_HFIXEDSZ;
 145         dpp = dnptrs;
 146         *dpp++ = buf;
 147         *dpp++ = NULL;
 148         lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
 149         /*
 150          * perform opcode specific processing
 151          */
 152         switch (op) {
 153         case ns_o_query:        /*FALLTHROUGH*/
 154         case ns_o_update:
 155                 if ((buflen -= NS_QFIXEDSZ) < 0)
 156                         return (-1);
 157                 if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
 158                         return (-1);
 159                 cp += n;
 160                 buflen -= n;
 161                 putshort(type, cp);
 162                 cp += NS_INT16SZ;
 163                 putshort(class, cp);
 164                 cp += NS_INT16SZ;
 165                 hp->qdcount = htons(1);
 166                 if (op == ns_o_query || data == NULL)
 167                         break;
 168                 /*
 169                  * Make an additional record for completion domain.
 170                  */
 171                 buflen -= NS_RRFIXEDSZ;
 172                 n = dn_comp((const char *)data, cp, buflen, dnptrs, lastdnptr);
 173                 if (n < 0)
 174                         return (-1);
 175                 cp += n;
 176                 buflen -= n;
 177                 putshort(ns_t_null, cp);
 178                 cp += NS_INT16SZ;
 179                 putshort(class, cp);
 180                 cp += NS_INT16SZ;
 181                 putlong(0, cp);
 182                 cp += NS_INT32SZ;
 183                 putshort(0, cp);
 184                 cp += NS_INT16SZ;
 185                 hp->arcount = htons(1);
 186                 break;
 187
 188         case ns_o_iquery:
 189                 /*
 190                  * Initialize answer section
 191                  */
 192                 if (buflen < 1 + NS_RRFIXEDSZ + datalen)
 193                         return (-1);
 194                 *cp++ = '\0';   /* no domain name */
 195                 putshort(type, cp);
 196                 cp += NS_INT16SZ;
 197                 putshort(class, cp);
 198                 cp += NS_INT16SZ;
 199                 putlong(0, cp);
 200                 cp += NS_INT32SZ;
 201                 putshort(datalen, cp);
 202                 cp += NS_INT16SZ;
 203                 if (datalen) {
 204                         memcpy(cp, data, datalen);
 205                         cp += datalen;
 206                 }
 207                 hp->ancount = htons(1);
 208                 break;
 209
 210         default:
 211                 return (-1);
 212         }
 213         return (cp - buf);
 214 }
 215
 216 #ifdef RES_USE_EDNS0
 217 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
 218 #ifndef T_OPT
 219 #define T_OPT   41
 220 #endif
 221
 222 int
 223 res_nopt(statp, n0, buf, buflen, anslen)
 224         res_state statp;
 225         int n0;
 226         u_char *buf;            /* buffer to put query */
 227         int buflen;             /* size of buffer */
 228         int anslen;             /* answer buffer length */
 229 {
 230         register HEADER *hp;
 231         register u_char *cp;
 232         u_int16_t flags = 0;
 233
 234 #ifdef DEBUG
 235         if ((statp->options & RES_DEBUG) != 0)
 236                 printf(";; res_nopt()\n");
 237 #endif
 238
 239         hp = (HEADER *) buf;
 240         cp = buf + n0;
 241         buflen -= n0;
 242
 243         if (buflen < 1 + NS_RRFIXEDSZ)
 244                 return -1;
 245
 246         *cp++ = 0;      /* "." */
 247         buflen--;
 248
 249         putshort(T_OPT, cp);    /* TYPE */
 250         cp += NS_INT16SZ;
 251         putshort(anslen & 0xffff, cp);  /* CLASS = UDP payload size */
 252         cp += NS_INT16SZ;
 253         *cp++ = ns_r_noerror;   /* extended RCODE */
 254         *cp++ = 0;              /* EDNS version */
 255         if (statp->options & RES_USE_DNSSEC) {
 256 #ifdef DEBUG
 257                 if (statp->options & RES_DEBUG)
 258                         printf(";; res_opt()... ENDS0 DNSSEC\n");
 259 #endif
 260                 flags |= NS_OPT_DNSSEC_OK;
 261         }
 262         putshort(flags, cp);
 263         cp += NS_INT16SZ;
 264         putshort(0, cp);        /* RDLEN */
 265         cp += NS_INT16SZ;
 266         hp->arcount = htons(ntohs(hp->arcount) + 1);
 267         buflen -= NS_RRFIXEDSZ;
 268
 269         return cp - buf;
 270 }
 271 #endif