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 <netdb.h>
  67 #include <resolv.h>
  68 #if defined(BSD) && (BSD >= 199103)
  69 # include <string.h>
  70 #else
  71 # include "../conf/portability.h"
  72 #endif
  73
  74 #if defined(USE_OPTIONS_H)
  75 # include <../conf/options.h>
  76 #endif
  77
  78 /*
  79  * Form all types of queries.
  80  * Returns the size of the result or -1.
  81  */
  82 int
  83 res_mkquery(op, dname, class, type, data, datalen, newrr_in, buf, buflen)
  84         int op;                 /* opcode of query */
  85         const char *dname;      /* domain name */
  86         int class, type;        /* class and type of query */
  87         const u_char *data;     /* resource record data */
  88         int datalen;            /* length of data */
  89         const u_char *newrr_in; /* new rr for modify or append */
  90         u_char *buf;            /* buffer to put query */
  91         int buflen;             /* size of buffer */
  92 {
  93         register HEADER *hp;
  94         register u_char *cp;
  95         register int n;
  96 #ifdef ALLOW_UPDATES
  97         struct rrec *newrr = (struct rrec *) newrr_in;
  98 #endif
  99         u_char *dnptrs[20], **dpp, **lastdnptr;
 100
 101         if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
 102                 h_errno = NETDB_INTERNAL;
 103                 return (-1);
 104         }
 105 #ifdef DEBUG
 106         if (_res.options & RES_DEBUG)
 107                 printf(";; res_mkquery(%d, %s, %d, %d)\n",
 108                        op, dname, class, type);
 109 #endif
 110         /*
 111          * Initialize header fields.
 112          */
 113         if ((buf == NULL) || (buflen < HFIXEDSZ))
 114                 return (-1);
 115         bzero(buf, HFIXEDSZ);
 116         hp = (HEADER *) buf;
 117         hp->id = htons(++_res.id);
 118         hp->opcode = op;
 119         hp->rd = (_res.options & RES_RECURSE) != 0;
 120         hp->rcode = NOERROR;
 121         cp = buf + HFIXEDSZ;
 122         buflen -= HFIXEDSZ;
 123         dpp = dnptrs;
 124         *dpp++ = buf;
 125         *dpp++ = NULL;
 126         lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
 127         /*
 128          * perform opcode specific processing
 129          */
 130         switch (op) {
 131         case QUERY:     /*FALLTHROUGH*/
 132         case NS_NOTIFY_OP:
 133                 if ((buflen -= QFIXEDSZ) < 0)
 134                         return (-1);
 135                 if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
 136                         return (-1);
 137                 cp += n;
 138                 buflen -= n;
 139                 __putshort(type, cp);
 140                 cp += INT16SZ;
 141                 __putshort(class, cp);
 142                 cp += INT16SZ;
 143                 hp->qdcount = htons(1);
 144                 if (op == QUERY || data == NULL)
 145                         break;
 146                 /*
 147                  * Make an additional record for completion domain.
 148                  */
 149                 buflen -= RRFIXEDSZ;
 150                 n = dn_comp((char *)data, cp, buflen, dnptrs, lastdnptr);
 151                 if (n < 0)
 152                         return (-1);
 153                 cp += n;
 154                 buflen -= n;
 155                 __putshort(T_NULL, cp);
 156                 cp += INT16SZ;
 157                 __putshort(class, cp);
 158                 cp += INT16SZ;
 159                 __putlong(0, cp);
 160                 cp += INT32SZ;
 161                 __putshort(0, cp);
 162                 cp += INT16SZ;
 163                 hp->arcount = htons(1);
 164                 break;
 165
 166         case IQUERY:
 167                 /*
 168                  * Initialize answer section
 169                  */
 170                 if (buflen < 1 + RRFIXEDSZ + datalen)
 171                         return (-1);
 172                 *cp++ = '\0';   /* no domain name */
 173                 __putshort(type, cp);
 174                 cp += INT16SZ;
 175                 __putshort(class, cp);
 176                 cp += INT16SZ;
 177                 __putlong(0, cp);
 178                 cp += INT32SZ;
 179                 __putshort(datalen, cp);
 180                 cp += INT16SZ;
 181                 if (datalen) {
 182                         bcopy(data, cp, datalen);
 183                         cp += datalen;
 184                 }
 185                 hp->ancount = htons(1);
 186                 break;
 187
 188 #ifdef ALLOW_UPDATES
 189         /*
 190          * For UPDATEM/UPDATEMA, do UPDATED/UPDATEDA followed by UPDATEA
 191          * (Record to be modified is followed by its replacement in msg.)
 192          */
 193         case UPDATEM:
 194         case UPDATEMA:
 195
 196         case UPDATED:
 197                 /*
 198                  * The res code for UPDATED and UPDATEDA is the same; user
 199                  * calls them differently: specifies data for UPDATED; server
 200                  * ignores data if specified for UPDATEDA.
 201                  */
 202         case UPDATEDA:
 203                 buflen -= RRFIXEDSZ + datalen;
 204                 if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
 205                         return (-1);
 206                 cp += n;
 207                 __putshort(type, cp);
 208                 cp += INT16SZ;
 209                 __putshort(class, cp);
 210                 cp += INT16SZ;
 211                 __putlong(0, cp);
 212                 cp += INT32SZ;
 213                 __putshort(datalen, cp);
 214                 cp += INT16SZ;
 215                 if (datalen) {
 216                         bcopy(data, cp, datalen);
 217                         cp += datalen;
 218                 }
 219                 if ( (op == UPDATED) || (op == UPDATEDA) ) {
 220                         hp->ancount = htons(0);
 221                         break;
 222                 }
 223                 /* Else UPDATEM/UPDATEMA, so drop into code for UPDATEA */
 224
 225         case UPDATEA:   /* Add new resource record */
 226                 buflen -= RRFIXEDSZ + datalen;
 227                 if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
 228                         return (-1);
 229                 cp += n;
 230                 __putshort(newrr->r_type, cp);
 231                 cp += INT16SZ;
 232                 __putshort(newrr->r_class, cp);
 233                 cp += INT16SZ;
 234                 __putlong(0, cp);
 235                 cp += INT32SZ;
 236                 __putshort(newrr->r_size, cp);
 237                 cp += INT16SZ;
 238                 if (newrr->r_size) {
 239                         bcopy(newrr->r_data, cp, newrr->r_size);
 240                         cp += newrr->r_size;
 241                 }
 242                 hp->ancount = htons(0);
 243                 break;
 244 #endif /* ALLOW_UPDATES */
 245         default:
 246                 return (-1);
 247         }
 248         return (cp - buf);
 249 }