resolv/res_mkquery.c

   1 /*
   2  * ++Copyright++ 1985, 1993
   3  * -
   4  * Copyright (c) 1985, 1993
   5  *    The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  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  * --Copyright--
  54  */
  55
  56 #if defined(LIBC_SCCS) && !defined(lint)
  57 static char sccsid[] = "@(#)res_mkquery.c       8.1 (Berkeley) 6/4/93";
  58 static char rcsid[] = "$Id$";
  59 #endif /* LIBC_SCCS and not lint */
  60
  61 #include <sys/param.h>
  62 #include <netinet/in.h>
  63 #include <arpa/nameser.h>
  64
  65 #include <stdio.h>
  66 #include <resolv.h>
  67 #if defined(BSD) && (BSD >= 199103)
  68 # include <string.h>
  69 #else
  70 # include "../conf/portability.h"
  71 #endif
  72
  73 #if defined(USE_OPTIONS_H)
  74 # include <../conf/options.h>
  75 #endif
  76
  77 /*
  78  * Form all types of queries.
  79  * Returns the size of the result or -1.
  80  */
  81 int
  82 res_mkquery(op, dname, class, type, data, datalen, newrr_in, buf, buflen)
  83         int op;                 /* opcode of query */
  84         const char *dname;      /* domain name */
  85         int class, type;        /* class and type of query */
  86         const u_char *data;     /* resource record data */
  87         int datalen;            /* length of data */
  88         const u_char *newrr_in; /* new rr for modify or append */
  89         u_char *buf;            /* buffer to put query */
  90         int buflen;             /* size of buffer */
  91 {
  92         register HEADER *hp;
  93         register u_char *cp;
  94         register int n;
  95         struct rrec *newrr = (struct rrec *) newrr_in;
  96         u_char *dnptrs[20], **dpp, **lastdnptr;
  97
  98 #ifdef DEBUG
  99         if (_res.options & RES_DEBUG)
 100                 printf(";; res_mkquery(%d, %s, %d, %d)\n",
 101                        op, dname, class, type);
 102 #endif
 103         if (!(_res.options & RES_INIT)) {
 104                 if (res_init() == -1)
 105                         return (-1);
 106         }
 107         /*
 108          * Initialize header fields.
 109          */
 110         if ((buf == NULL) || (buflen < HFIXEDSZ))
 111                 return (-1);
 112         bzero(buf, HFIXEDSZ);
 113         hp = (HEADER *) buf;
 114         hp->id = htons(++_res.id);
 115         hp->opcode = op;
 116         hp->pr = (_res.options & RES_PRIMARY) != 0;
 117         hp->rd = (_res.options & RES_RECURSE) != 0;
 118         hp->rcode = NOERROR;
 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          * perform opcode specific processing
 127          */
 128         switch (op) {
 129         case QUERY:     /*FALLTHROUGH*/
 130         case NS_NOTIFY_OP:
 131                 if ((buflen -= QFIXEDSZ) < 0)
 132                         return (-1);
 133                 if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
 134                         return (-1);
 135                 cp += n;
 136                 buflen -= n;
 137                 __putshort(type, cp);
 138                 cp += INT16SZ;
 139                 __putshort(class, cp);
 140                 cp += INT16SZ;
 141                 hp->qdcount = htons(1);
 142                 if (op == QUERY || data == NULL)
 143                         break;
 144                 /*
 145                  * Make an additional record for completion domain.
 146                  */
 147                 buflen -= RRFIXEDSZ;
 148                 n = dn_comp((char *)data, cp, buflen, dnptrs, lastdnptr);
 149                 if (n < 0)
 150                         return (-1);
 151                 cp += n;
 152                 buflen -= n;
 153                 __putshort(T_NULL, cp);
 154                 cp += INT16SZ;
 155                 __putshort(class, cp);
 156                 cp += INT16SZ;
 157                 __putlong(0, cp);
 158                 cp += INT32SZ;
 159                 __putshort(0, cp);
 160                 cp += INT16SZ;
 161                 hp->arcount = htons(1);
 162                 break;
 163
 164         case IQUERY:
 165                 /*
 166                  * Initialize answer section
 167                  */
 168                 if (buflen < 1 + RRFIXEDSZ + datalen)
 169                         return (-1);
 170                 *cp++ = '\0';   /* no domain name */
 171                 __putshort(type, cp);
 172                 cp += INT16SZ;
 173                 __putshort(class, cp);
 174                 cp += INT16SZ;
 175                 __putlong(0, cp);
 176                 cp += INT32SZ;
 177                 __putshort(datalen, cp);
 178                 cp += INT16SZ;
 179                 if (datalen) {
 180                         bcopy(data, cp, datalen);
 181                         cp += datalen;
 182                 }
 183                 hp->ancount = htons(1);
 184                 break;
 185
 186 #ifdef ALLOW_UPDATES
 187         /*
 188          * For UPDATEM/UPDATEMA, do UPDATED/UPDATEDA followed by UPDATEA
 189          * (Record to be modified is followed by its replacement in msg.)
 190          */
 191         case UPDATEM:
 192         case UPDATEMA:
 193
 194         case UPDATED:
 195                 /*
 196                  * The res code for UPDATED and UPDATEDA is the same; user
 197                  * calls them differently: specifies data for UPDATED; server
 198                  * ignores data if specified for UPDATEDA.
 199                  */
 200         case UPDATEDA:
 201                 buflen -= RRFIXEDSZ + datalen;
 202                 if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
 203                         return (-1);
 204                 cp += n;
 205                 __putshort(type, cp);
 206                 cp += INT16SZ;
 207                 __putshort(class, cp);
 208                 cp += INT16SZ;
 209                 __putlong(0, cp);
 210                 cp += INT32SZ;
 211                 __putshort(datalen, cp);
 212                 cp += INT16SZ;
 213                 if (datalen) {
 214                         bcopy(data, cp, datalen);
 215                         cp += datalen;
 216                 }
 217                 if ( (op == UPDATED) || (op == UPDATEDA) ) {
 218                         hp->ancount = htons(0);
 219                         break;
 220                 }
 221                 /* Else UPDATEM/UPDATEMA, so drop into code for UPDATEA */
 222
 223         case UPDATEA:   /* Add new resource record */
 224                 buflen -= RRFIXEDSZ + datalen;
 225                 if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
 226                         return (-1);
 227                 cp += n;
 228                 __putshort(newrr->r_type, cp);
 229                 cp += INT16SZ;
 230                 __putshort(newrr->r_class, cp);
 231                 cp += INT16SZ;
 232                 __putlong(0, cp);
 233                 cp += INT32SZ;
 234                 __putshort(newrr->r_size, cp);
 235                 cp += INT16SZ;
 236                 if (newrr->r_size) {
 237                         bcopy(newrr->r_data, cp, newrr->r_size);
 238                         cp += newrr->r_size;
 239                 }
 240                 hp->ancount = htons(0);
 241                 break;
 242 #endif /* ALLOW_UPDATES */
 243         default:
 244                 return (-1);
 245         }
 246         return (cp - buf);
 247 }