1 /* 2 * @(#)res_mkquery.c 8.1 (Berkeley) 6/4/93 3 * $Id: res_mkquery.c,v 1.6.672.1 2008/04/03 02:12:21 marka Exp $ 4 */ 5 6 /* 7 * Copyright (c) 1985, 1993 8 * The Regents of the University of California. All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 /* 36 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 37 * 38 * Permission to use, copy, modify, and distribute this software for any 39 * purpose with or without fee is hereby granted, provided that the above 40 * copyright notice and this permission notice appear in all copies, and that 41 * the name of Digital Equipment Corporation not be used in advertising or 42 * publicity pertaining to distribution of the document or software without 43 * specific, written prior permission. 44 * 45 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 46 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 47 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 48 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 49 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 50 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 51 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 52 * SOFTWARE. 53 */ 54 55 /* 56 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 57 * Portions Copyright (c) 1996-1999 by Internet Software Consortium. 58 * 59 * Permission to use, copy, modify, and distribute this software for any 60 * purpose with or without fee is hereby granted, provided that the above 61 * copyright notice and this permission notice appear in all copies. 62 * 63 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 64 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 65 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 66 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 67 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 68 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 69 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 70 */ 71 72 #include "port_before.h" 73 #include <sys/types.h> 74 #include <sys/param.h> 75 #include <netinet/in.h> 76 #include <arpa/nameser.h> 77 #include <netdb.h> 78 #include <resolv.h> 79 #include <stdio.h> 80 #include <string.h> 81 #include "port_after.h" 82 83 /* Options. Leave them on. */ 84 #define DEBUG 85 86 extern const char *_res_opcodes[]; 87 88 /*% 89 * Form all types of queries. 90 * Returns the size of the result or -1. 91 */ 92 int 93 res_nmkquery(res_state statp, 94 int op, /*!< opcode of query */ 95 const char *dname, /*!< domain name */ 96 int class, int type, /*!< class and type of query */ 97 const u_char *data, /*!< resource record data */ 98 int datalen, /*!< length of data */ 99 const u_char *newrr_in, /*!< new rr for modify or append */ 100 u_char *buf, /*!< buffer to put query */ 101 int buflen) /*!< size of buffer */ 102 { 103 HEADER *hp; 104 u_char *cp, *ep; 105 int n; 106 u_char *dnptrs[20], **dpp, **lastdnptr; 107 108 UNUSED(newrr_in); 109 110 #ifdef DEBUG 111 if (statp->options & RES_DEBUG) 112 printf(";; res_nmkquery(%s, %s, %s, %s)\n", 113 _res_opcodes[op], dname, p_class(class), p_type(type)); 114 #endif 115 /* 116 * Initialize header fields. 117 */ 118 if ((buf == NULL) || (buflen < HFIXEDSZ)) 119 return (-1); 120 memset(buf, 0, HFIXEDSZ); 121 hp = (HEADER *) buf; 122 hp->id = htons(++statp->id); 123 hp->opcode = op; 124 hp->rd = (statp->options & RES_RECURSE) != 0U; 125 hp->rcode = NOERROR; 126 cp = buf + HFIXEDSZ; 127 ep = buf + buflen; 128 dpp = dnptrs; 129 *dpp++ = buf; 130 *dpp++ = NULL; 131 lastdnptr = dnptrs + NELEM(dnptrs); 132 /* 133 * perform opcode specific processing 134 */ 135 switch (op) { 136 case QUERY: /*FALLTHROUGH*/ 137 case NS_NOTIFY_OP: 138 if (ep - cp < QFIXEDSZ) 139 return (-1); 140 if ((n = dn_comp(dname, cp, ep - cp - QFIXEDSZ, dnptrs, 141 lastdnptr)) < 0) 142 return (-1); 143 cp += n; 144 ns_put16(type, cp); 145 cp += INT16SZ; 146 ns_put16(class, cp); 147 cp += INT16SZ; 148 hp->qdcount = htons(1); 149 if (op == QUERY || data == NULL) 150 break; 151 /* 152 * Make an additional record for completion domain. 153 */ 154 if ((ep - cp) < RRFIXEDSZ) 155 return (-1); 156 n = dn_comp((const char *)data, cp, ep - cp - RRFIXEDSZ, 157 dnptrs, lastdnptr); 158 if (n < 0) 159 return (-1); 160 cp += n; 161 ns_put16(T_NULL, cp); 162 cp += INT16SZ; 163 ns_put16(class, cp); 164 cp += INT16SZ; 165 ns_put32(0, cp); 166 cp += INT32SZ; 167 ns_put16(0, cp); 168 cp += INT16SZ; 169 hp->arcount = htons(1); 170 break; 171 172 case IQUERY: 173 /* 174 * Initialize answer section 175 */ 176 if (ep - cp < 1 + RRFIXEDSZ + datalen) 177 return (-1); 178 *cp++ = '\0'; /*%< no domain name */ 179 ns_put16(type, cp); 180 cp += INT16SZ; 181 ns_put16(class, cp); 182 cp += INT16SZ; 183 ns_put32(0, cp); 184 cp += INT32SZ; 185 ns_put16(datalen, cp); 186 cp += INT16SZ; 187 if (datalen) { 188 memcpy(cp, data, datalen); 189 cp += datalen; 190 } 191 hp->ancount = htons(1); 192 break; 193 194 default: 195 return (-1); 196 } 197 return (cp - buf); 198 } 199 200 #ifdef RES_USE_EDNS0 201 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */ 202 203 int 204 res_nopt(res_state statp, 205 int n0, /*%< current offset in buffer */ 206 u_char *buf, /*%< buffer to put query */ 207 int buflen, /*%< size of buffer */ 208 int anslen) /*%< UDP answer buffer size */ 209 { 210 HEADER *hp; 211 u_char *cp, *ep; 212 u_int16_t flags = 0; 213 214 #ifdef DEBUG 215 if ((statp->options & RES_DEBUG) != 0U) 216 printf(";; res_nopt()\n"); 217 #endif 218 219 hp = (HEADER *) buf; 220 cp = buf + n0; 221 ep = buf + buflen; 222 223 if ((ep - cp) < 1 + RRFIXEDSZ) 224 return (-1); 225 226 *cp++ = 0; /*%< "." */ 227 ns_put16(ns_t_opt, cp); /*%< TYPE */ 228 cp += INT16SZ; 229 if (anslen > 0xffff) 230 anslen = 0xffff; 231 ns_put16(anslen & 0xffff, cp); /*%< CLASS = UDP payload size */ 232 cp += INT16SZ; 233 *cp++ = NOERROR; /*%< extended RCODE */ 234 *cp++ = 0; /*%< EDNS version */ 235 236 if (statp->options & RES_USE_DNSSEC) { 237 #ifdef DEBUG 238 if (statp->options & RES_DEBUG) 239 printf(";; res_opt()... ENDS0 DNSSEC\n"); 240 #endif 241 flags |= NS_OPT_DNSSEC_OK; 242 } 243 ns_put16(flags, cp); 244 cp += INT16SZ; 245 246 ns_put16(0U, cp); /*%< RDLEN */ 247 cp += INT16SZ; 248 249 hp->arcount = htons(ntohs(hp->arcount) + 1); 250 251 return (cp - buf); 252 } 253 254 /* 255 * Construct variable data (RDATA) block for OPT psuedo-RR, append it 256 * to the buffer, then update the RDLEN field (previously set to zero by 257 * res_nopt()) with the new RDATA length. 258 */ 259 int 260 res_nopt_rdata(res_state statp, 261 int n0, /*%< current offset in buffer */ 262 u_char *buf, /*%< buffer to put query */ 263 int buflen, /*%< size of buffer */ 264 u_char *rdata, /*%< ptr to start of opt rdata */ 265 u_short code, /*%< OPTION-CODE */ 266 u_short len, /*%< OPTION-LENGTH */ 267 u_char *data) /*%< OPTION_DATA */ 268 { 269 u_char *cp, *ep; 270 271 #ifdef DEBUG 272 if ((statp->options & RES_DEBUG) != 0U) 273 printf(";; res_nopt_rdata()\n"); 274 #endif 275 276 cp = buf + n0; 277 ep = buf + buflen; 278 279 if ((ep - cp) < (4 + len)) 280 return (-1); 281 282 if (rdata < (buf + 2) || rdata >= ep) 283 return (-1); 284 285 ns_put16(code, cp); 286 cp += INT16SZ; 287 288 ns_put16(len, cp); 289 cp += INT16SZ; 290 291 memcpy(cp, data, len); 292 cp += len; 293 294 len = cp - rdata; 295 ns_put16(len, rdata - 2); /* Update RDLEN field */ 296 297 return (cp - buf); 298 } 299 #endif 300 301 /*! \file */ 302