src/kits/network/netresolv/resolv/res_mkquery.c

   1 /*      $NetBSD: res_mkquery.c,v 1.15 2015/02/24 17:56:20 christos Exp $        */
   2
   3 /*
   4  * Portions Copyright (C) 2004, 2005, 2008  Internet Systems Consortium, Inc. ("ISC")
   5  * Portions Copyright (C) 1996, 1997, 1988, 1999, 2001, 2003  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  17  * PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /*
  21  * Copyright (c) 1985, 1993
  22  *    The Regents of the University of California.  All rights reserved.
  23  *
  24  * Redistribution and use in source and binary forms, with or without
  25  * modification, are permitted provided that the following conditions
  26  * are met:
  27  * 1. Redistributions of source code must retain the above copyright
  28  *    notice, this list of conditions and the following disclaimer.
  29  * 2. Redistributions in binary form must reproduce the above copyright
  30  *    notice, this list of conditions and the following disclaimer in the
  31  *    documentation and/or other materials provided with the distribution.
  32  * 3. Neither the name of the University nor the names of its contributors
  33  *    may be used to endorse or promote products derived from this software
  34  *    without specific prior written permission.
  35  *
  36  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  37  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  39  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  40  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  41  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  42  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  44  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  45  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  46  * SUCH DAMAGE.
  47  */
  48
  49 /*
  50  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  51  *
  52  * Permission to use, copy, modify, and distribute this software for any
  53  * purpose with or without fee is hereby granted, provided that the above
  54  * copyright notice and this permission notice appear in all copies, and that
  55  * the name of Digital Equipment Corporation not be used in advertising or
  56  * publicity pertaining to distribution of the document or software without
  57  * specific, written prior permission.
  58  *
  59  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  60  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  61  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  62  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  63  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  64  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  65  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  66  * SOFTWARE.
  67  */
  68
  69 #if defined(LIBC_SCCS) && !defined(lint)
  70 static const char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93";
  71 static const char rcsid[] = "$Id: res_mkquery.c,v 1.10 2008/12/11 09:59:00 marka Exp $";
  72 #endif /* LIBC_SCCS and not lint */
  73
  74 #include "port_before.h"
  75 #include <sys/types.h>
  76 #include <sys/param.h>
  77 #include <netinet/in.h>
  78 #include <arpa/nameser.h>
  79 #include <assert.h>
  80 #include <netdb.h>
  81 #include <resolv.h>
  82 #include <stdio.h>
  83 #include <string.h>
  84 #include "port_after.h"
  85
  86 /* Options.  Leave them on. */
  87 //#define DEBUG
  88
  89 extern const char *_res_opcodes[];
  90
  91 /*%
  92  * Form all types of queries.
  93  * Returns the size of the result or -1.
  94  */
  95 int
  96 res_nmkquery(res_state statp,
  97              int op,                    /*!< opcode of query  */
  98              const char *dname,         /*!< domain name  */
  99              int class, int type,       /*!< class and type of query  */
 100              const u_char *data,        /*!< resource record data  */
 101              int datalen,               /*!< length of data  */
 102              const u_char *newrr_in,    /*!< new rr for modify or append  */
 103              u_char *buf,               /*!< buffer to put query  */
 104              int buflen)                /*!< size of buffer  */
 105 {
 106         register HEADER *hp;
 107         register u_char *cp, *ep;
 108         register int n;
 109         u_char *dnptrs[20], **dpp, **lastdnptr;
 110
 111         UNUSED(newrr_in);
 112
 113 #ifdef DEBUG
 114         if (statp->options & RES_DEBUG)
 115                 printf(";; res_nmkquery(%s, %s, %s, %s)\n",
 116                        _res_opcodes[op], dname, p_class(class), p_type(type));
 117 #endif
 118         /*
 119          * Initialize header fields.
 120          */
 121         if ((buf == NULL) || (buflen < HFIXEDSZ))
 122                 return (-1);
 123         memset(buf, 0, HFIXEDSZ);
 124         hp = (HEADER *)(void *)buf;
 125         statp->id = res_nrandomid(statp);
 126         hp->id = htons(statp->id);
 127         hp->opcode = op;
 128         hp->rd = (statp->options & RES_RECURSE) != 0U;
 129         hp->rcode = NOERROR;
 130         cp = buf + HFIXEDSZ;
 131         ep = buf + buflen;
 132         dpp = dnptrs;
 133         *dpp++ = buf;
 134         *dpp++ = NULL;
 135         lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0];
 136         /*
 137          * perform opcode specific processing
 138          */
 139         switch (op) {
 140         case QUERY:     /*FALLTHROUGH*/
 141         case NS_NOTIFY_OP:
 142                 if (ep - cp < QFIXEDSZ)
 143                         return (-1);
 144                 if ((n = dn_comp(dname, cp, (int)(ep - cp - QFIXEDSZ), dnptrs,
 145                     lastdnptr)) < 0)
 146                         return (-1);
 147                 cp += n;
 148                 ns_put16(type, cp);
 149                 cp += INT16SZ;
 150                 ns_put16(class, cp);
 151                 cp += INT16SZ;
 152                 hp->qdcount = htons(1);
 153                 if (op == QUERY || data == NULL)
 154                         break;
 155                 /*
 156                  * Make an additional record for completion domain.
 157                  */
 158                 if ((ep - cp) < RRFIXEDSZ)
 159                         return (-1);
 160                 n = dn_comp((const char *)data, cp, (int)(ep - cp - RRFIXEDSZ),
 161                             dnptrs, lastdnptr);
 162                 if (n < 0)
 163                         return (-1);
 164                 cp += n;
 165                 ns_put16(T_NULL, cp);
 166                 cp += INT16SZ;
 167                 ns_put16(class, cp);
 168                 cp += INT16SZ;
 169                 ns_put32(0, cp);
 170                 cp += INT32SZ;
 171                 ns_put16(0, cp);
 172                 cp += INT16SZ;
 173                 hp->arcount = htons(1);
 174                 break;
 175
 176         case IQUERY:
 177                 /*
 178                  * Initialize answer section
 179                  */
 180                 if (ep - cp < 1 + RRFIXEDSZ + datalen)
 181                         return (-1);
 182                 *cp++ = '\0';   /*%< no domain name */
 183                 ns_put16(type, cp);
 184                 cp += INT16SZ;
 185                 ns_put16(class, cp);
 186                 cp += INT16SZ;
 187                 ns_put32(0, cp);
 188                 cp += INT32SZ;
 189                 ns_put16(datalen, cp);
 190                 cp += INT16SZ;
 191                 if (datalen) {
 192                         memcpy(cp, data, (size_t)datalen);
 193                         cp += datalen;
 194                 }
 195                 hp->ancount = htons(1);
 196                 break;
 197
 198         default:
 199                 return (-1);
 200         }
 201         assert(INT_MIN <= (cp - buf) && (cp - buf) <= INT_MAX);
 202         return (int)(cp - buf);
 203 }
 204
 205 #ifdef RES_USE_EDNS0
 206 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
 207
 208 int
 209 res_nopt(res_state statp,
 210          int n0,                /*%< current offset in buffer */
 211          u_char *buf,           /*%< buffer to put query */
 212          int buflen,            /*%< size of buffer */
 213          int anslen)            /*%< UDP answer buffer size */
 214 {
 215         register HEADER *hp;
 216         register u_char *cp, *ep;
 217         u_int16_t flags = 0;
 218
 219 #ifdef DEBUG
 220         if ((statp->options & RES_DEBUG) != 0U)
 221                 printf(";; res_nopt()\n");
 222 #endif
 223
 224         hp = (HEADER *)(void *)buf;
 225         cp = buf + n0;
 226         ep = buf + buflen;
 227
 228         if ((ep - cp) < 1 + RRFIXEDSZ)
 229                 return (-1);
 230
 231         *cp++ = 0;                              /*%< "." */
 232         ns_put16(ns_t_opt, cp);                 /*%< TYPE */
 233         cp += INT16SZ;
 234         if (anslen > 0xffff)
 235                 anslen = 0xffff;
 236         ns_put16(anslen, cp);                   /*%< CLASS = UDP payload size */
 237         cp += INT16SZ;
 238         *cp++ = NOERROR;                        /*%< extended RCODE */
 239         *cp++ = 0;                              /*%< EDNS version */
 240
 241         if (statp->options & RES_USE_DNSSEC) {
 242 #ifdef DEBUG
 243                 if (statp->options & RES_DEBUG)
 244                         printf(";; res_opt()... ENDS0 DNSSEC\n");
 245 #endif
 246                 flags |= NS_OPT_DNSSEC_OK;
 247         }
 248         ns_put16(flags, cp);
 249         cp += INT16SZ;
 250
 251         ns_put16(0U, cp);                       /*%< RDLEN */
 252         cp += INT16SZ;
 253
 254         hp->arcount = htons(ntohs(hp->arcount) + 1);
 255
 256         assert(INT_MIN <= (cp - buf) && (cp - buf) <= INT_MAX);
 257         return (int)(cp - buf);
 258 }
 259
 260 /*
 261  * Construct variable data (RDATA) block for OPT psuedo-RR, append it
 262  * to the buffer, then update the RDLEN field (previously set to zero by
 263  * res_nopt()) with the new RDATA length.
 264  */
 265 int
 266 res_nopt_rdata(res_state statp,
 267           int n0,               /*%< current offset in buffer */
 268           u_char *buf,          /*%< buffer to put query */
 269           int buflen,           /*%< size of buffer */
 270           u_char *rdata,        /*%< ptr to start of opt rdata */
 271           u_short code,         /*%< OPTION-CODE */
 272           u_short len,          /*%< OPTION-LENGTH */
 273           u_char *data)         /*%< OPTION_DATA */
 274 {
 275         register u_char *cp, *ep;
 276
 277 #ifdef DEBUG
 278         if ((statp->options & RES_DEBUG) != 0U)
 279                 printf(";; res_nopt_rdata()\n");
 280 #endif
 281
 282         cp = buf + n0;
 283         ep = buf + buflen;
 284
 285         if ((ep - cp) < (4 + len))
 286                 return (-1);
 287
 288         if (rdata < (buf + 2) || rdata >= ep)
 289                 return (-1);
 290
 291         ns_put16(code, cp);
 292         cp += INT16SZ;
 293
 294         ns_put16(len, cp);
 295         cp += INT16SZ;
 296
 297         memcpy(cp, data, (size_t)len);
 298         cp += len;
 299
 300         assert(0 <= (cp - rdata) && (cp - rdata) <= USHRT_MAX);
 301         len = (u_short)(cp - rdata);
 302         ns_put16(len, rdata - 2);       /* Update RDLEN field */
 303
 304         assert(INT_MIN <= (cp - buf) && (cp - buf) <= INT_MAX);
 305         return (int)(cp - buf);
 306 }
 307 #endif
 308
 309 /*! \file */