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  * 4. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  * -
  31  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  32  *
  33  * Permission to use, copy, modify, and distribute this software for any
  34  * purpose with or without fee is hereby granted, provided that the above
  35  * copyright notice and this permission notice appear in all copies, and that
  36  * the name of Digital Equipment Corporation not be used in advertising or
  37  * publicity pertaining to distribution of the document or software without
  38  * specific, written prior permission.
  39  *
  40  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  41  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  42  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  43  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  44  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  45  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  46  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  47  * SOFTWARE.
  48  * -
  49  * --Copyright--
  50  */
  51
  52 #if defined(LIBC_SCCS) && !defined(lint)
  53 static char sccsid[] = "@(#)res_mkquery.c       8.1 (Berkeley) 6/4/93";
  54 static char rcsid[] = "$Id$";
  55 #endif /* LIBC_SCCS and not lint */
  56
  57 #include <sys/types.h>
  58 #include <sys/param.h>
  59 #include <netinet/in.h>
  60 #include <arpa/nameser.h>
  61
  62 #include <stdio.h>
  63 #include <netdb.h>
  64 #include <resolv.h>
  65 #if defined(BSD) && (BSD >= 199103)
  66 # include <string.h>
  67 #else
  68 # include "../conf/portability.h"
  69 #endif
  70
  71 #if defined(USE_OPTIONS_H)
  72 # include <../conf/options.h>
  73 #endif
  74
  75 /*
  76  * Form all types of queries.
  77  * Returns the size of the result or -1.
  78  */
  79 int
  80 res_mkquery(op, dname, class, type, data, datalen, newrr_in, buf, buflen)
  81         int op;                 /* opcode of query */
  82         const char *dname;      /* domain name */
  83         int class, type;        /* class and type of query */
  84         const u_char *data;     /* resource record data */
  85         int datalen;            /* length of data */
  86         const u_char *newrr_in; /* new rr for modify or append */
  87         u_char *buf;            /* buffer to put query */
  88         int buflen;             /* size of buffer */
  89 {
  90         register HEADER *hp;
  91         register u_char *cp;
  92         register int n;
  93         u_char *dnptrs[20], **dpp, **lastdnptr;
  94
  95         if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
  96                 __set_h_errno (NETDB_INTERNAL);
  97                 return (-1);
  98         }
  99 #ifdef DEBUG
 100         if (_res.options & RES_DEBUG)
 101                 printf(";; res_mkquery(%d, %s, %d, %d)\n",
 102                        op, dname, class, type);
 103 #endif
 104         /*
 105          * Initialize header fields.
 106          */
 107         if ((buf == NULL) || (buflen < HFIXEDSZ))
 108                 return (-1);
 109         bzero(buf, HFIXEDSZ);
 110         hp = (HEADER *) buf;
 111         hp->id = htons(++_res.id);
 112         hp->opcode = op;
 113         hp->rd = (_res.options & RES_RECURSE) != 0;
 114         hp->rcode = NOERROR;
 115         cp = buf + HFIXEDSZ;
 116         buflen -= HFIXEDSZ;
 117         dpp = dnptrs;
 118         *dpp++ = buf;
 119         *dpp++ = NULL;
 120         lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
 121         /*
 122          * perform opcode specific processing
 123          */
 124         switch (op) {
 125         case QUERY:     /*FALLTHROUGH*/
 126         case NS_NOTIFY_OP:
 127                 if ((buflen -= QFIXEDSZ) < 0)
 128                         return (-1);
 129                 if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
 130                         return (-1);
 131                 cp += n;
 132                 buflen -= n;
 133                 __putshort(type, cp);
 134                 cp += INT16SZ;
 135                 __putshort(class, cp);
 136                 cp += INT16SZ;
 137                 hp->qdcount = htons(1);
 138                 if (op == QUERY || data == NULL)
 139                         break;
 140                 /*
 141                  * Make an additional record for completion domain.
 142                  */
 143                 buflen -= RRFIXEDSZ;
 144                 n = dn_comp((char *)data, cp, buflen, dnptrs, lastdnptr);
 145                 if (n < 0)
 146                         return (-1);
 147                 cp += n;
 148                 buflen -= n;
 149                 __putshort(T_NULL, cp);
 150                 cp += INT16SZ;
 151                 __putshort(class, cp);
 152                 cp += INT16SZ;
 153                 __putlong(0, cp);
 154                 cp += INT32SZ;
 155                 __putshort(0, cp);
 156                 cp += INT16SZ;
 157                 hp->arcount = htons(1);
 158                 break;
 159
 160         case IQUERY:
 161                 /*
 162                  * Initialize answer section
 163                  */
 164                 if (buflen < 1 + RRFIXEDSZ + datalen)
 165                         return (-1);
 166                 *cp++ = '\0';   /* no domain name */
 167                 __putshort(type, cp);
 168                 cp += INT16SZ;
 169                 __putshort(class, cp);
 170                 cp += INT16SZ;
 171                 __putlong(0, cp);
 172                 cp += INT32SZ;
 173                 __putshort(datalen, cp);
 174                 cp += INT16SZ;
 175                 if (datalen) {
 176                         bcopy(data, cp, datalen);
 177                         cp += datalen;
 178                 }
 179                 hp->ancount = htons(1);
 180                 break;
 181
 182         default:
 183                 return (-1);
 184         }
 185         return (cp - buf);
 186 }