1 /*-
2 * SPDX-License-Identifier: (ISC AND BSD-3-Clause)
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. Neither the name of the University nor the names of its contributors
33 * may be used to endorse or promote products derived from this software
34 * without specific prior written permission.
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
37 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
40 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46 * SUCH DAMAGE.
47 */
48
49 /*
50 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
51 *
52 * Permission to use, copy, modify, and distribute this software for any
53 * purpose with or without fee is hereby granted, provided that the above
54 * copyright notice and this permission notice appear in all copies, and that
55 * the name of Digital Equipment Corporation not be used in advertising or
56 * publicity pertaining to distribution of the document or software without
57 * specific, written prior permission.
58 *
59 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
60 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
61 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
62 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
63 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
64 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
65 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
66 * SOFTWARE.
67 */
68
69 #include "port_before.h"
70 #include <sys/param.h>
71 #include <netinet/in.h>
72 #include <arpa/nameser.h>
73 #include <netdb.h>
74 #include <resolv.h>
75 #include <stdio.h>
76 #include <string.h>
77 #include "port_after.h"
78
79 /* Options. Leave them on. */
80 #ifndef DEBUG
81 #define DEBUG
82 #endif
83
84 extern const char *_res_opcodes[];
85
86 /*%
87 * Form all types of queries.
88 * Returns the size of the result or -1.
89 */
90 int
res_nmkquery(res_state statp,int op,const char * dname,int class,int type,const u_char * data,int datalen,const u_char * newrr_in,u_char * buf,int buflen)91 res_nmkquery(res_state statp,
92 int op, /*!< opcode of query */
93 const char *dname, /*!< domain name */
94 int class, int type, /*!< class and type of query */
95 const u_char *data, /*!< resource record data */
96 int datalen, /*!< length of data */
97 const u_char *newrr_in, /*!< new rr for modify or append */
98 u_char *buf, /*!< buffer to put query */
99 int buflen) /*!< size of buffer */
100 {
101 HEADER *hp;
102 u_char *cp, *ep;
103 int n;
104 u_char *dnptrs[20], **dpp, **lastdnptr;
105
106 UNUSED(newrr_in);
107
108 #ifdef DEBUG
109 if (statp->options & RES_DEBUG)
110 printf(";; res_nmkquery(%s, %s, %s, %s)\n",
111 _res_opcodes[op], dname, p_class(class), p_type(type));
112 #endif
113 /*
114 * Initialize header fields.
115 */
116 if ((buf == NULL) || (buflen < HFIXEDSZ))
117 return (-1);
118 memset(buf, 0, HFIXEDSZ);
119 hp = (HEADER *) buf;
120 statp->id = res_nrandomid(statp);
121 hp->id = htons(statp->id);
122 hp->opcode = op;
123 hp->rd = (statp->options & RES_RECURSE) != 0U;
124 hp->rcode = NOERROR;
125 cp = buf + HFIXEDSZ;
126 ep = buf + buflen;
127 dpp = dnptrs;
128 *dpp++ = buf;
129 *dpp++ = NULL;
130 lastdnptr = dnptrs + nitems(dnptrs);
131 /*
132 * perform opcode specific processing
133 */
134 switch (op) {
135 case QUERY: /*FALLTHROUGH*/
136 case NS_NOTIFY_OP:
137 if (ep - cp < QFIXEDSZ)
138 return (-1);
139 if ((n = dn_comp(dname, cp, ep - cp - QFIXEDSZ, dnptrs,
140 lastdnptr)) < 0)
141 return (-1);
142 cp += n;
143 ns_put16(type, cp);
144 cp += INT16SZ;
145 ns_put16(class, cp);
146 cp += INT16SZ;
147 hp->qdcount = htons(1);
148 if (op == QUERY || data == NULL)
149 break;
150 /*
151 * Make an additional record for completion domain.
152 */
153 if ((ep - cp) < RRFIXEDSZ)
154 return (-1);
155 n = dn_comp((const char *)data, cp, ep - cp - RRFIXEDSZ,
156 dnptrs, lastdnptr);
157 if (n < 0)
158 return (-1);
159 cp += n;
160 ns_put16(T_NULL, cp);
161 cp += INT16SZ;
162 ns_put16(class, cp);
163 cp += INT16SZ;
164 ns_put32(0, cp);
165 cp += INT32SZ;
166 ns_put16(0, cp);
167 cp += INT16SZ;
168 hp->arcount = htons(1);
169 break;
170
171 case IQUERY:
172 /*
173 * Initialize answer section
174 */
175 if (ep - cp < 1 + RRFIXEDSZ + datalen)
176 return (-1);
177 *cp++ = '\0'; /*%< no domain name */
178 ns_put16(type, cp);
179 cp += INT16SZ;
180 ns_put16(class, cp);
181 cp += INT16SZ;
182 ns_put32(0, cp);
183 cp += INT32SZ;
184 ns_put16(datalen, cp);
185 cp += INT16SZ;
186 if (datalen) {
187 memcpy(cp, data, datalen);
188 cp += datalen;
189 }
190 hp->ancount = htons(1);
191 break;
192
193 default:
194 return (-1);
195 }
196 return (cp - buf);
197 }
198
199 #ifdef RES_USE_EDNS0
200 /* attach OPT pseudo-RR, as documented in RFC2671 (EDNS0). */
201
202 int
res_nopt(res_state statp,int n0,u_char * buf,int buflen,int anslen)203 res_nopt(res_state statp,
204 int n0, /*%< current offset in buffer */
205 u_char *buf, /*%< buffer to put query */
206 int buflen, /*%< size of buffer */
207 int anslen) /*%< UDP answer buffer size */
208 {
209 HEADER *hp;
210 u_char *cp, *ep;
211 u_int16_t flags = 0;
212
213 #ifdef DEBUG
214 if ((statp->options & RES_DEBUG) != 0U)
215 printf(";; res_nopt()\n");
216 #endif
217
218 hp = (HEADER *) buf;
219 cp = buf + n0;
220 ep = buf + buflen;
221
222 if ((ep - cp) < 1 + RRFIXEDSZ)
223 return (-1);
224
225 *cp++ = 0; /*%< "." */
226 ns_put16(ns_t_opt, cp); /*%< TYPE */
227 cp += INT16SZ;
228 if (anslen > 0xffff)
229 anslen = 0xffff; /* limit to 16bit value */
230 ns_put16(anslen & 0xffff, cp); /*%< CLASS = UDP payload size */
231 cp += INT16SZ;
232 *cp++ = NOERROR; /*%< extended RCODE */
233 *cp++ = 0; /*%< EDNS version */
234
235 if (statp->options & RES_USE_DNSSEC) {
236 #ifdef DEBUG
237 if (statp->options & RES_DEBUG)
238 printf(";; res_opt()... ENDS0 DNSSEC\n");
239 #endif
240 flags |= NS_OPT_DNSSEC_OK;
241 }
242 ns_put16(flags, cp);
243 cp += INT16SZ;
244
245 ns_put16(0U, cp); /*%< RDLEN */
246 cp += INT16SZ;
247
248 hp->arcount = htons(ntohs(hp->arcount) + 1);
249
250 return (cp - buf);
251 }
252
253 /*
254 * Construct variable data (RDATA) block for OPT pseudo-RR, append it
255 * to the buffer, then update the RDLEN field (previously set to zero by
256 * res_nopt()) with the new RDATA length.
257 */
258 int
res_nopt_rdata(res_state statp,int n0,u_char * buf,int buflen,u_char * rdata,u_short code,u_short len,u_char * data)259 res_nopt_rdata(res_state statp,
260 int n0, /*%< current offset in buffer */
261 u_char *buf, /*%< buffer to put query */
262 int buflen, /*%< size of buffer */
263 u_char *rdata, /*%< ptr to start of opt rdata */
264 u_short code, /*%< OPTION-CODE */
265 u_short len, /*%< OPTION-LENGTH */
266 u_char *data) /*%< OPTION_DATA */
267 {
268 register u_char *cp, *ep;
269
270 #ifdef DEBUG
271 if ((statp->options & RES_DEBUG) != 0U)
272 printf(";; res_nopt_rdata()\n");
273 #endif
274
275 cp = buf + n0;
276 ep = buf + buflen;
277
278 if ((ep - cp) < (4 + len))
279 return (-1);
280
281 if (rdata < (buf + 2) || rdata >= ep)
282 return (-1);
283
284 ns_put16(code, cp);
285 cp += INT16SZ;
286
287 ns_put16(len, cp);
288 cp += INT16SZ;
289
290 memcpy(cp, data, len);
291 cp += len;
292
293 len = cp - rdata;
294 ns_put16(len, rdata - 2); /* Update RDLEN field */
295
296 return (cp - buf);
297 }
298 #endif
299
300 /*! \file */
301