1 /* $NetBSD: res_mkquery.c,v 1.12 2009/04/12 19:43:37 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. All advertising materials mentioning features or use of this software 33 * must display the following acknowledgement: 34 * This product includes software developed by the University of 35 * California, Berkeley and its contributors. 36 * 4. Neither the name of the University nor the names of its contributors 37 * may be used to endorse or promote products derived from this software 38 * without specific prior written permission. 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 */ 52 53 /* 54 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 55 * 56 * Permission to use, copy, modify, and distribute this software for any 57 * purpose with or without fee is hereby granted, provided that the above 58 * copyright notice and this permission notice appear in all copies, and that 59 * the name of Digital Equipment Corporation not be used in advertising or 60 * publicity pertaining to distribution of the document or software without 61 * specific, written prior permission. 62 * 63 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 64 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 65 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 66 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 67 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 68 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 69 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 70 * 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 1.10 2008/12/11 09:59:00 marka Exp"; 78 #else 79 __RCSID("$NetBSD: res_mkquery.c,v 1.12 2009/04/12 19:43:37 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 statp->id = res_nrandomid(statp); 145 hp->id = htons(statp->id); 146 hp->opcode = op; 147 hp->rd = (statp->options & RES_RECURSE) != 0U; 148 hp->rcode = NOERROR; 149 cp = buf + HFIXEDSZ; 150 ep = buf + buflen; 151 dpp = dnptrs; 152 *dpp++ = buf; 153 *dpp++ = NULL; 154 lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0]; 155 /* 156 * perform opcode specific processing 157 */ 158 switch (op) { 159 case QUERY: /*FALLTHROUGH*/ 160 case NS_NOTIFY_OP: 161 if (ep - cp < QFIXEDSZ) 162 return (-1); 163 if ((n = dn_comp(dname, cp, ep - cp - QFIXEDSZ, dnptrs, 164 lastdnptr)) < 0) 165 return (-1); 166 cp += n; 167 ns_put16(type, cp); 168 cp += INT16SZ; 169 ns_put16(class, cp); 170 cp += INT16SZ; 171 hp->qdcount = htons(1); 172 if (op == QUERY || data == NULL) 173 break; 174 /* 175 * Make an additional record for completion domain. 176 */ 177 if ((ep - cp) < RRFIXEDSZ) 178 return (-1); 179 n = dn_comp((const char *)data, cp, ep - cp - RRFIXEDSZ, 180 dnptrs, lastdnptr); 181 if (n < 0) 182 return (-1); 183 cp += n; 184 ns_put16(T_NULL, cp); 185 cp += INT16SZ; 186 ns_put16(class, cp); 187 cp += INT16SZ; 188 ns_put32(0, cp); 189 cp += INT32SZ; 190 ns_put16(0, cp); 191 cp += INT16SZ; 192 hp->arcount = htons(1); 193 break; 194 195 case IQUERY: 196 /* 197 * Initialize answer section 198 */ 199 if (ep - cp < 1 + RRFIXEDSZ + datalen) 200 return (-1); 201 *cp++ = '\0'; /*%< no domain name */ 202 ns_put16(type, cp); 203 cp += INT16SZ; 204 ns_put16(class, cp); 205 cp += INT16SZ; 206 ns_put32(0, cp); 207 cp += INT32SZ; 208 ns_put16(datalen, cp); 209 cp += INT16SZ; 210 if (datalen) { 211 memcpy(cp, data, (size_t)datalen); 212 cp += datalen; 213 } 214 hp->ancount = htons(1); 215 break; 216 217 default: 218 return (-1); 219 } 220 return (cp - buf); 221 } 222 223 #ifdef RES_USE_EDNS0 224 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */ 225 226 int 227 res_nopt(res_state statp, 228 int n0, /*%< current offset in buffer */ 229 u_char *buf, /*%< buffer to put query */ 230 int buflen, /*%< size of buffer */ 231 int anslen) /*%< UDP answer buffer size */ 232 { 233 register HEADER *hp; 234 register u_char *cp, *ep; 235 u_int16_t flags = 0; 236 237 #ifdef DEBUG 238 if ((statp->options & RES_DEBUG) != 0U) 239 printf(";; res_nopt()\n"); 240 #endif 241 242 hp = (HEADER *)(void *)buf; 243 cp = buf + n0; 244 ep = buf + buflen; 245 246 if ((ep - cp) < 1 + RRFIXEDSZ) 247 return (-1); 248 249 *cp++ = 0; /*%< "." */ 250 ns_put16(ns_t_opt, cp); /*%< TYPE */ 251 cp += INT16SZ; 252 ns_put16(anslen & 0xffff, cp); /*%< CLASS = UDP payload size */ 253 cp += INT16SZ; 254 *cp++ = NOERROR; /*%< extended RCODE */ 255 *cp++ = 0; /*%< EDNS version */ 256 257 if (statp->options & RES_USE_DNSSEC) { 258 #ifdef DEBUG 259 if (statp->options & RES_DEBUG) 260 printf(";; res_opt()... ENDS0 DNSSEC\n"); 261 #endif 262 flags |= NS_OPT_DNSSEC_OK; 263 } 264 ns_put16(flags, cp); 265 cp += INT16SZ; 266 267 ns_put16(0U, cp); /*%< RDLEN */ 268 cp += INT16SZ; 269 270 hp->arcount = htons(ntohs(hp->arcount) + 1); 271 272 return (cp - buf); 273 } 274 275 /* 276 * Construct variable data (RDATA) block for OPT psuedo-RR, append it 277 * to the buffer, then update the RDLEN field (previously set to zero by 278 * res_nopt()) with the new RDATA length. 279 */ 280 int 281 res_nopt_rdata(res_state statp, 282 int n0, /*%< current offset in buffer */ 283 u_char *buf, /*%< buffer to put query */ 284 int buflen, /*%< size of buffer */ 285 u_char *rdata, /*%< ptr to start of opt rdata */ 286 u_short code, /*%< OPTION-CODE */ 287 u_short len, /*%< OPTION-LENGTH */ 288 u_char *data) /*%< OPTION_DATA */ 289 { 290 register u_char *cp, *ep; 291 292 #ifdef DEBUG 293 if ((statp->options & RES_DEBUG) != 0U) 294 printf(";; res_nopt_rdata()\n"); 295 #endif 296 297 cp = buf + n0; 298 ep = buf + buflen; 299 300 if ((ep - cp) < (4 + len)) 301 return (-1); 302 303 if (rdata < (buf + 2) || rdata >= ep) 304 return (-1); 305 306 ns_put16(code, cp); 307 cp += INT16SZ; 308 309 ns_put16(len, cp); 310 cp += INT16SZ; 311 312 memcpy(cp, data, (size_t)len); 313 cp += len; 314 315 len = cp - rdata; 316 ns_put16(len, rdata - 2); /* Update RDLEN field */ 317 318 return (cp - buf); 319 } 320 #endif 321 322 /*! \file */ 323