1 /* $NetBSD: res_mkquery.c,v 1.10 2008/06/21 23:37:53 christos Exp $ */ 2 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 36 /* 37 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 38 * 39 * Permission to use, copy, modify, and distribute this software for any 40 * purpose with or without fee is hereby granted, provided that the above 41 * copyright notice and this permission notice appear in all copies, and that 42 * the name of Digital Equipment Corporation not be used in advertising or 43 * publicity pertaining to distribution of the document or software without 44 * specific, written prior permission. 45 * 46 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 47 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 48 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 49 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 50 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 51 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 52 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 53 * SOFTWARE. 54 */ 55 56 /* 57 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 58 * Portions Copyright (c) 1996-1999 by Internet Software Consortium. 59 * 60 * Permission to use, copy, modify, and distribute this software for any 61 * purpose with or without fee is hereby granted, provided that the above 62 * copyright notice and this permission notice appear in all copies. 63 * 64 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 65 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 66 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 67 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 68 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 69 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 70 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 71 */ 72 73 #include <sys/cdefs.h> 74 #if defined(LIBC_SCCS) && !defined(lint) 75 #ifdef notdef 76 static const char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93"; 77 static const char rcsid[] = "Id: res_mkquery.c,v 1.6.672.1 2008/04/03 02:12:21 marka Exp"; 78 #else 79 __RCSID("$NetBSD: res_mkquery.c,v 1.10 2008/06/21 23:37:53 christos Exp $"); 80 #endif 81 #endif /* LIBC_SCCS and not lint */ 82 83 #include "port_before.h" 84 85 #include "namespace.h" 86 #include <sys/types.h> 87 #include <sys/param.h> 88 #include <netinet/in.h> 89 #include <arpa/nameser.h> 90 #include <netdb.h> 91 #include <resolv.h> 92 #include <stdio.h> 93 #include <string.h> 94 #include "port_after.h" 95 96 #if 0 97 #ifdef __weak_alias 98 __weak_alias(res_nmkquery,_res_nmkquery) 99 __weak_alias(res_nopt,_res_nopt) 100 #endif 101 #endif 102 103 /* Options. Leave them on. */ 104 #ifndef DEBUG 105 #define DEBUG 106 #endif 107 108 extern const char *_res_opcodes[]; 109 110 /*% 111 * Form all types of queries. 112 * Returns the size of the result or -1. 113 */ 114 int 115 res_nmkquery(res_state statp, 116 int op, /*!< opcode of query */ 117 const char *dname, /*!< domain name */ 118 int class, int type, /*!< class and type of query */ 119 const u_char *data, /*!< resource record data */ 120 int datalen, /*!< length of data */ 121 const u_char *newrr_in, /*!< new rr for modify or append */ 122 u_char *buf, /*!< buffer to put query */ 123 int buflen) /*!< size of buffer */ 124 { 125 register HEADER *hp; 126 register u_char *cp, *ep; 127 register int n; 128 u_char *dnptrs[20], **dpp, **lastdnptr; 129 130 UNUSED(newrr_in); 131 132 #ifdef DEBUG 133 if (statp->options & RES_DEBUG) 134 printf(";; res_nmkquery(%s, %s, %s, %s)\n", 135 _res_opcodes[op], dname, p_class(class), p_type(type)); 136 #endif 137 /* 138 * Initialize header fields. 139 */ 140 if ((buf == NULL) || (buflen < HFIXEDSZ)) 141 return (-1); 142 memset(buf, 0, HFIXEDSZ); 143 hp = (HEADER *)(void *)buf; 144 hp->id = htons(++statp->id); 145 hp->opcode = op; 146 hp->rd = (statp->options & RES_RECURSE) != 0U; 147 hp->rcode = NOERROR; 148 cp = buf + HFIXEDSZ; 149 ep = buf + buflen; 150 dpp = dnptrs; 151 *dpp++ = buf; 152 *dpp++ = NULL; 153 lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0]; 154 /* 155 * perform opcode specific processing 156 */ 157 switch (op) { 158 case QUERY: /*FALLTHROUGH*/ 159 case NS_NOTIFY_OP: 160 if (ep - cp < QFIXEDSZ) 161 return (-1); 162 if ((n = dn_comp(dname, cp, ep - cp - QFIXEDSZ, dnptrs, 163 lastdnptr)) < 0) 164 return (-1); 165 cp += n; 166 ns_put16(type, cp); 167 cp += INT16SZ; 168 ns_put16(class, cp); 169 cp += INT16SZ; 170 hp->qdcount = htons(1); 171 if (op == QUERY || data == NULL) 172 break; 173 /* 174 * Make an additional record for completion domain. 175 */ 176 if ((ep - cp) < RRFIXEDSZ) 177 return (-1); 178 n = dn_comp((const char *)data, cp, ep - cp - RRFIXEDSZ, 179 dnptrs, lastdnptr); 180 if (n < 0) 181 return (-1); 182 cp += n; 183 ns_put16(T_NULL, cp); 184 cp += INT16SZ; 185 ns_put16(class, cp); 186 cp += INT16SZ; 187 ns_put32(0, cp); 188 cp += INT32SZ; 189 ns_put16(0, cp); 190 cp += INT16SZ; 191 hp->arcount = htons(1); 192 break; 193 194 case IQUERY: 195 /* 196 * Initialize answer section 197 */ 198 if (ep - cp < 1 + RRFIXEDSZ + datalen) 199 return (-1); 200 *cp++ = '\0'; /*%< no domain name */ 201 ns_put16(type, cp); 202 cp += INT16SZ; 203 ns_put16(class, cp); 204 cp += INT16SZ; 205 ns_put32(0, cp); 206 cp += INT32SZ; 207 ns_put16(datalen, cp); 208 cp += INT16SZ; 209 if (datalen) { 210 memcpy(cp, data, (size_t)datalen); 211 cp += datalen; 212 } 213 hp->ancount = htons(1); 214 break; 215 216 default: 217 return (-1); 218 } 219 return (cp - buf); 220 } 221 222 #ifdef RES_USE_EDNS0 223 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */ 224 225 int 226 res_nopt(res_state statp, 227 int n0, /*%< current offset in buffer */ 228 u_char *buf, /*%< buffer to put query */ 229 int buflen, /*%< size of buffer */ 230 int anslen) /*%< UDP answer buffer size */ 231 { 232 register HEADER *hp; 233 register u_char *cp, *ep; 234 u_int16_t flags = 0; 235 236 #ifdef DEBUG 237 if ((statp->options & RES_DEBUG) != 0U) 238 printf(";; res_nopt()\n"); 239 #endif 240 241 hp = (HEADER *)(void *)buf; 242 cp = buf + n0; 243 ep = buf + buflen; 244 245 if ((ep - cp) < 1 + RRFIXEDSZ) 246 return (-1); 247 248 *cp++ = 0; /*%< "." */ 249 ns_put16(ns_t_opt, cp); /*%< TYPE */ 250 cp += INT16SZ; 251 ns_put16(anslen & 0xffff, cp); /*%< CLASS = UDP payload size */ 252 cp += INT16SZ; 253 *cp++ = NOERROR; /*%< extended RCODE */ 254 *cp++ = 0; /*%< EDNS version */ 255 256 if (statp->options & RES_USE_DNSSEC) { 257 #ifdef DEBUG 258 if (statp->options & RES_DEBUG) 259 printf(";; res_opt()... ENDS0 DNSSEC\n"); 260 #endif 261 flags |= NS_OPT_DNSSEC_OK; 262 } 263 ns_put16(flags, cp); 264 cp += INT16SZ; 265 266 ns_put16(0U, cp); /*%< RDLEN */ 267 cp += INT16SZ; 268 269 hp->arcount = htons(ntohs(hp->arcount) + 1); 270 271 return (cp - buf); 272 } 273 274 /* 275 * Construct variable data (RDATA) block for OPT psuedo-RR, append it 276 * to the buffer, then update the RDLEN field (previously set to zero by 277 * res_nopt()) with the new RDATA length. 278 */ 279 int 280 res_nopt_rdata(res_state statp, 281 int n0, /*%< current offset in buffer */ 282 u_char *buf, /*%< buffer to put query */ 283 int buflen, /*%< size of buffer */ 284 u_char *rdata, /*%< ptr to start of opt rdata */ 285 u_short code, /*%< OPTION-CODE */ 286 u_short len, /*%< OPTION-LENGTH */ 287 u_char *data) /*%< OPTION_DATA */ 288 { 289 register u_char *cp, *ep; 290 291 #ifdef DEBUG 292 if ((statp->options & RES_DEBUG) != 0U) 293 printf(";; res_nopt_rdata()\n"); 294 #endif 295 296 cp = buf + n0; 297 ep = buf + buflen; 298 299 if ((ep - cp) < (4 + len)) 300 return (-1); 301 302 if (rdata < (buf + 2) || rdata >= ep) 303 return (-1); 304 305 ns_put16(code, cp); 306 cp += INT16SZ; 307 308 ns_put16(len, cp); 309 cp += INT16SZ; 310 311 (void)memcpy(cp, data, (size_t)len); 312 cp += len; 313 314 len = cp - rdata; 315 ns_put16(len, rdata - 2); /* Update RDLEN field */ 316 317 return (cp - buf); 318 } 319 #endif 320 321 /*! \file */ 322