1 /* $NetBSD: res_mkquery.c,v 1.6 2006/01/24 17:40:32 christos Exp $ */ 2 3 /* 4 * Copyright (c) 2008 Android Open Source Project (query id randomization) 5 * Copyright (c) 1985, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 /* 38 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 39 * 40 * Permission to use, copy, modify, and distribute this software for any 41 * purpose with or without fee is hereby granted, provided that the above 42 * copyright notice and this permission notice appear in all copies, and that 43 * the name of Digital Equipment Corporation not be used in advertising or 44 * publicity pertaining to distribution of the document or software without 45 * specific, written prior permission. 46 * 47 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 48 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 49 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 50 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 51 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 52 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 53 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 54 * SOFTWARE. 55 */ 56 57 /* 58 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 59 * Portions Copyright (c) 1996-1999 by Internet Software Consortium. 60 * 61 * Permission to use, copy, modify, and distribute this software for any 62 * purpose with or without fee is hereby granted, provided that the above 63 * copyright notice and this permission notice appear in all copies. 64 * 65 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 66 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 67 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 68 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 69 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 70 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 71 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 72 */ 73 74 #include <sys/cdefs.h> 75 #if defined(LIBC_SCCS) && !defined(lint) 76 #ifdef notdef 77 static const char sccsid[] = "@(#)res_mkquery.c 8.1 (Berkeley) 6/4/93"; 78 static const char rcsid[] = "Id: res_mkquery.c,v 1.1.2.2.4.2 2004/03/16 12:34:18 marka Exp"; 79 #else 80 __RCSID("$NetBSD: res_mkquery.c,v 1.6 2006/01/24 17:40:32 christos Exp $"); 81 #endif 82 #endif /* LIBC_SCCS and not lint */ 83 84 85 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 #ifdef ANDROID_CHANGES 92 #include "resolv_private.h" 93 #else 94 #include <resolv.h> 95 #endif 96 #include <stdio.h> 97 #include <string.h> 98 99 /* Options. Leave them on. */ 100 #ifndef DEBUG 101 #define DEBUG 102 #endif 103 104 #ifndef lint 105 #define UNUSED(a) (void)&a 106 #else 107 #define UNUSED(a) a = a 108 #endif 109 110 extern const char *_res_opcodes[]; 111 112 /* 113 * Form all types of queries. 114 * Returns the size of the result or -1. 115 */ 116 int 117 res_nmkquery(res_state statp, 118 int op, /* opcode of query */ 119 const char *dname, /* domain name */ 120 int class, int type, /* class and type of query */ 121 const u_char *data, /* resource record data */ 122 int datalen, /* length of data */ 123 const u_char *newrr_in, /* new rr for modify or append */ 124 u_char *buf, /* buffer to put query */ 125 int buflen) /* size of buffer */ 126 { 127 register HEADER *hp; 128 register u_char *cp, *ep; 129 register int n; 130 u_char *dnptrs[20], **dpp, **lastdnptr; 131 132 UNUSED(newrr_in); 133 134 #ifdef DEBUG 135 if (statp->options & RES_DEBUG) 136 printf(";; res_nmkquery(%s, %s, %s, %s)\n", 137 _res_opcodes[op], dname, p_class(class), p_type(type)); 138 #endif 139 /* 140 * Initialize header fields. 141 */ 142 if ((buf == NULL) || (buflen < HFIXEDSZ)) 143 return (-1); 144 memset(buf, 0, HFIXEDSZ); 145 hp = (HEADER *)(void *)buf; 146 hp->id = htons(res_randomid()); 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, 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 ns_put16(anslen & 0xffff, cp); /* CLASS = UDP payload size */ 258 cp += INT16SZ; 259 *cp++ = NOERROR; /* extended RCODE */ 260 *cp++ = 0; /* EDNS version */ 261 if (statp->options & RES_USE_DNSSEC) { 262 #ifdef DEBUG 263 if (statp->options & RES_DEBUG) 264 printf(";; res_opt()... ENDS0 DNSSEC\n"); 265 #endif 266 flags |= NS_OPT_DNSSEC_OK; 267 } 268 ns_put16(flags, cp); 269 cp += INT16SZ; 270 ns_put16(0, cp); /* RDLEN */ 271 cp += INT16SZ; 272 hp->arcount = htons(ntohs(hp->arcount) + 1); 273 274 return (cp - buf); 275 } 276 #endif 277
