1 /* $NetBSD: res_mkquery.c,v 1.6 2006/01/24 17:40:32 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 1.1.2.2.4.2 2004/03/16 12:34:18 marka Exp"; 78 #else 79 __RCSID("$NetBSD: res_mkquery.c,v 1.6 2006/01/24 17:40:32 christos Exp $"); 80 #endif 81 #endif /* LIBC_SCCS and not lint */ 82 83 84 85 #include <sys/types.h> 86 #include <sys/param.h> 87 #include <netinet/in.h> 88 #include <arpa/nameser.h> 89 #include <netdb.h> 90 #ifdef ANDROID_CHANGES 91 #include "resolv_private.h" 92 #else 93 #include <resolv.h> 94 #endif 95 #include <stdio.h> 96 #include <string.h> 97 98 /* Options. Leave them on. */ 99 #ifndef DEBUG 100 #define DEBUG 101 #endif 102 103 #ifndef lint 104 #define UNUSED(a) (void)&a 105 #else 106 #define UNUSED(a) a = a 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 hp->id = htons(res_randomid()); 146 hp->opcode = op; 147 hp->rd = (statp->options & RES_RECURSE) != 0U; 148 hp->ad = (statp->options & RES_USE_DNSSEC) != 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, 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, 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 return (cp - buf); 222 } 223 224 #ifdef RES_USE_EDNS0 225 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */ 226 #ifndef T_OPT 227 #define T_OPT 41 228 #endif 229 230 int 231 res_nopt(res_state statp, 232 int n0, /* current offset in buffer */ 233 u_char *buf, /* buffer to put query */ 234 int buflen, /* size of buffer */ 235 int anslen) /* UDP answer buffer size */ 236 { 237 register HEADER *hp; 238 register u_char *cp, *ep; 239 u_int16_t flags = 0; 240 241 #ifdef DEBUG 242 if ((statp->options & RES_DEBUG) != 0U) 243 printf(";; res_nopt()\n"); 244 #endif 245 246 hp = (HEADER *)(void *)buf; 247 cp = buf + n0; 248 ep = buf + buflen; 249 250 if ((ep - cp) < 1 + RRFIXEDSZ) 251 return (-1); 252 253 *cp++ = 0; /* "." */ 254 255 ns_put16(T_OPT, cp); /* TYPE */ 256 cp += INT16SZ; 257 if (anslen > 0xffff) 258 anslen = 0xffff; 259 ns_put16(anslen, cp); /* CLASS = UDP payload size */ 260 cp += INT16SZ; 261 *cp++ = NOERROR; /* extended RCODE */ 262 *cp++ = 0; /* EDNS version */ 263 if (statp->options & RES_USE_DNSSEC) { 264 #ifdef DEBUG 265 if (statp->options & RES_DEBUG) 266 printf(";; res_opt()... ENDS0 DNSSEC\n"); 267 #endif 268 flags |= NS_OPT_DNSSEC_OK; 269 } 270 ns_put16(flags, cp); 271 cp += INT16SZ; 272 #ifdef EDNS0_PADDING 273 { 274 u_int16_t minlen = (cp - buf) + 3 * INT16SZ; 275 u_int16_t extra = minlen % EDNS0_PADDING; 276 u_int16_t padlen = (EDNS0_PADDING - extra) % EDNS0_PADDING; 277 if (minlen > buflen) { 278 return (-1); 279 } 280 padlen = MIN(padlen, buflen - minlen); 281 ns_put16(padlen + 2 * INT16SZ, cp); /* RDLEN */ 282 cp += INT16SZ; 283 ns_put16(NS_OPT_PADDING, cp); /* OPTION-CODE */ 284 cp += INT16SZ; 285 ns_put16(padlen, cp); /* OPTION-LENGTH */ 286 cp += INT16SZ; 287 memset(cp, 0, padlen); 288 cp += padlen; 289 } 290 #else 291 ns_put16(0, cp); /* RDLEN */ 292 cp += INT16SZ; 293 #endif 294 hp->arcount = htons(ntohs(hp->arcount) + 1); 295 296 return (cp - buf); 297 } 298 #endif 299
