1 /* $NetBSD: res_mkquery.c,v 1.13 2012/03/13 21:13:43 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 1.13 2012/03/13 21:13:43 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 <assert.h> 91 #include <netdb.h> 92 #include <resolv.h> 93 #include <stdio.h> 94 #include <string.h> 95 #include "port_after.h" 96 97 #if 0 98 #ifdef __weak_alias 99 __weak_alias(res_nmkquery,_res_nmkquery) 100 __weak_alias(res_nopt,_res_nopt) 101 #endif 102 #endif 103 104 /* Options. Leave them on. */ 105 #ifndef DEBUG 106 #define DEBUG 107 #endif 108 109 extern const char *_res_opcodes[]; 110 111 /*% 112 * Form all types of queries. 113 * Returns the size of the result or -1. 114 */ 115 int 116 res_nmkquery(res_state statp, 117 int op, /*!< opcode of query */ 118 const char *dname, /*!< domain name */ 119 int class, int type, /*!< class and type of query */ 120 const u_char *data, /*!< resource record data */ 121 int datalen, /*!< length of data */ 122 const u_char *newrr_in, /*!< new rr for modify or append */ 123 u_char *buf, /*!< buffer to put query */ 124 int buflen) /*!< size of buffer */ 125 { 126 register HEADER *hp; 127 register u_char *cp, *ep; 128 register int n; 129 u_char *dnptrs[20], **dpp, **lastdnptr; 130 131 UNUSED(newrr_in); 132 133 #ifdef DEBUG 134 if (statp->options & RES_DEBUG) 135 printf(";; res_nmkquery(%s, %s, %s, %s)\n", 136 _res_opcodes[op], dname, p_class(class), p_type(type)); 137 #endif 138 /* 139 * Initialize header fields. 140 */ 141 if ((buf == NULL) || (buflen < HFIXEDSZ)) 142 return (-1); 143 memset(buf, 0, HFIXEDSZ); 144 hp = (HEADER *)(void *)buf; 145 statp->id = res_nrandomid(statp); 146 hp->id = htons(statp->id); 147 hp->opcode = op; 148 hp->rd = (statp->options & RES_RECURSE) != 0U; 149 hp->rcode = NOERROR; 150 cp = buf + HFIXEDSZ; 151 ep = buf + buflen; 152 dpp = dnptrs; 153 *dpp++ = buf; 154 *dpp++ = NULL; 155 lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0]; 156 /* 157 * perform opcode specific processing 158 */ 159 switch (op) { 160 case QUERY: /*FALLTHROUGH*/ 161 case NS_NOTIFY_OP: 162 if (ep - cp < QFIXEDSZ) 163 return (-1); 164 if ((n = dn_comp(dname, cp, (int)(ep - cp - QFIXEDSZ), dnptrs, 165 lastdnptr)) < 0) 166 return (-1); 167 cp += n; 168 ns_put16(type, cp); 169 cp += INT16SZ; 170 ns_put16(class, cp); 171 cp += INT16SZ; 172 hp->qdcount = htons(1); 173 if (op == QUERY || data == NULL) 174 break; 175 /* 176 * Make an additional record for completion domain. 177 */ 178 if ((ep - cp) < RRFIXEDSZ) 179 return (-1); 180 n = dn_comp((const char *)data, cp, (int)(ep - cp - RRFIXEDSZ), 181 dnptrs, lastdnptr); 182 if (n < 0) 183 return (-1); 184 cp += n; 185 ns_put16(T_NULL, cp); 186 cp += INT16SZ; 187 ns_put16(class, cp); 188 cp += INT16SZ; 189 ns_put32(0, cp); 190 cp += INT32SZ; 191 ns_put16(0, cp); 192 cp += INT16SZ; 193 hp->arcount = htons(1); 194 break; 195 196 case IQUERY: 197 /* 198 * Initialize answer section 199 */ 200 if (ep - cp < 1 + RRFIXEDSZ + datalen) 201 return (-1); 202 *cp++ = '\0'; /*%< no domain name */ 203 ns_put16(type, cp); 204 cp += INT16SZ; 205 ns_put16(class, cp); 206 cp += INT16SZ; 207 ns_put32(0, cp); 208 cp += INT32SZ; 209 ns_put16(datalen, cp); 210 cp += INT16SZ; 211 if (datalen) { 212 memcpy(cp, data, (size_t)datalen); 213 cp += datalen; 214 } 215 hp->ancount = htons(1); 216 break; 217 218 default: 219 return (-1); 220 } 221 _DIAGASSERT(__type_fit(int, cp - buf)); 222 return (int)(cp - buf); 223 } 224 225 #ifdef RES_USE_EDNS0 226 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */ 227 228 int 229 res_nopt(res_state statp, 230 int n0, /*%< current offset in buffer */ 231 u_char *buf, /*%< buffer to put query */ 232 int buflen, /*%< size of buffer */ 233 int anslen) /*%< UDP answer buffer size */ 234 { 235 register HEADER *hp; 236 register u_char *cp, *ep; 237 u_int16_t flags = 0; 238 239 #ifdef DEBUG 240 if ((statp->options & RES_DEBUG) != 0U) 241 printf(";; res_nopt()\n"); 242 #endif 243 244 hp = (HEADER *)(void *)buf; 245 cp = buf + n0; 246 ep = buf + buflen; 247 248 if ((ep - cp) < 1 + RRFIXEDSZ) 249 return (-1); 250 251 *cp++ = 0; /*%< "." */ 252 ns_put16(ns_t_opt, cp); /*%< TYPE */ 253 cp += INT16SZ; 254 ns_put16(anslen & 0xffff, cp); /*%< CLASS = UDP payload size */ 255 cp += INT16SZ; 256 *cp++ = NOERROR; /*%< extended RCODE */ 257 *cp++ = 0; /*%< EDNS version */ 258 259 if (statp->options & RES_USE_DNSSEC) { 260 #ifdef DEBUG 261 if (statp->options & RES_DEBUG) 262 printf(";; res_opt()... ENDS0 DNSSEC\n"); 263 #endif 264 flags |= NS_OPT_DNSSEC_OK; 265 } 266 ns_put16(flags, cp); 267 cp += INT16SZ; 268 269 ns_put16(0U, cp); /*%< RDLEN */ 270 cp += INT16SZ; 271 272 hp->arcount = htons(ntohs(hp->arcount) + 1); 273 274 _DIAGASSERT(__type_fit(int, cp - buf)); 275 return (int)(cp - buf); 276 } 277 278 /* 279 * Construct variable data (RDATA) block for OPT psuedo-RR, append it 280 * to the buffer, then update the RDLEN field (previously set to zero by 281 * res_nopt()) with the new RDATA length. 282 */ 283 int 284 res_nopt_rdata(res_state statp, 285 int n0, /*%< current offset in buffer */ 286 u_char *buf, /*%< buffer to put query */ 287 int buflen, /*%< size of buffer */ 288 u_char *rdata, /*%< ptr to start of opt rdata */ 289 u_short code, /*%< OPTION-CODE */ 290 u_short len, /*%< OPTION-LENGTH */ 291 u_char *data) /*%< OPTION_DATA */ 292 { 293 register u_char *cp, *ep; 294 295 #ifdef DEBUG 296 if ((statp->options & RES_DEBUG) != 0U) 297 printf(";; res_nopt_rdata()\n"); 298 #endif 299 300 cp = buf + n0; 301 ep = buf + buflen; 302 303 if ((ep - cp) < (4 + len)) 304 return (-1); 305 306 if (rdata < (buf + 2) || rdata >= ep) 307 return (-1); 308 309 ns_put16(code, cp); 310 cp += INT16SZ; 311 312 ns_put16(len, cp); 313 cp += INT16SZ; 314 315 memcpy(cp, data, (size_t)len); 316 cp += len; 317 318 _DIAGASSERT(__type_fit(u_short, cp - rdata)); 319 len = (u_short)(cp - rdata); 320 ns_put16(len, rdata - 2); /* Update RDLEN field */ 321 322 _DIAGASSERT(__type_fit(int, cp - buf)); 323 return (int)(cp - buf); 324 } 325 #endif 326 327 /*! \file */ 328