1/* $OpenBSD: resolv.h,v 1.23 2021/11/22 20:18:27 jca Exp $ */
2
3/*
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * 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. Neither the name of the project nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32/*
33 * ++Copyright++ 1983, 1987, 1989, 1993
34 * -
35 * Copyright (c) 1983, 1987, 1989, 1993
36 * The Regents of the University of California. All rights reserved.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 * 1. Redistributions of source code must retain the above copyright
42 * notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 * notice, this list of conditions and the following disclaimer in the
45 * documentation and/or other materials provided with the distribution.
46 * 3. Neither the name of the University nor the names of its contributors
47 * may be used to endorse or promote products derived from this software
48 * without specific prior written permission.
49 *
50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60 * SUCH DAMAGE.
61 * -
62 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
63 *
64 * Permission to use, copy, modify, and distribute this software for any
65 * purpose with or without fee is hereby granted, provided that the above
66 * copyright notice and this permission notice appear in all copies, and that
67 * the name of Digital Equipment Corporation not be used in advertising or
68 * publicity pertaining to distribution of the document or software without
69 * specific, written prior permission.
70 *
71 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
72 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
73 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
74 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
75 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
76 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
77 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
78 * SOFTWARE.
79 * -
80 * --Copyright--
81 */
82
83/*
84 * @(#)resolv.h 8.1 (Berkeley) 6/2/93
85 * $From: resolv.h,v 8.17 1996/11/26 10:11:20 vixie Exp $
86 */
87
88#ifndef _RESOLV_H_
89#define _RESOLV_H_
90
91#include <sys/types.h>
92#include <sys/socket.h>
93#include <stdio.h>
94
95/*
96 * Revision information. This is the release date in YYYYMMDD format.
97 * It can change every day so the right thing to do with it is use it
98 * in preprocessor commands such as "#if (__RES > 19931104)". Do not
99 * compare for equality; rather, use it to determine whether your resolver
100 * is new enough to contain a certain feature.
101 */
102
103#define __RES 19960801
104
105/*
106 * Resolver configuration file.
107 * Normally not present, but may contain the address of the
108 * initial name server(s) to query and the domain search list.
109 */
110
111#ifndef _PATH_RESCONF
112#define _PATH_RESCONF "/etc/resolv.conf"
113#endif
114
115/*
116 * Global defines and variables for resolver stub.
117 */
118#define MAXNS 3 /* max # name servers we'll track */
119#define MAXDFLSRCH 3 /* # default domain levels to try */
120#define MAXDNSRCH 6 /* max # domains in search path */
121#define LOCALDOMAINPARTS 2 /* min levels in name that is "local" */
122#define MAXDNSLUS 4 /* max # of host lookup types */
123
124#define RES_TIMEOUT 5 /* min. seconds between retries */
125#define MAXRESOLVSORT 10 /* number of net to sort on */
126#define RES_MAXNDOTS 15 /* should reflect bit field size */
127
128struct __res_state {
129 int retrans; /* retransmission time interval */
130 int retry; /* number of times to retransmit */
131 unsigned int options; /* option flags - see below. */
132 int nscount; /* number of name servers */
133 int family[2]; /* specifies which address
134 * families will be queried and
135 * in which order */
136 struct sockaddr_in
137 nsaddr_list[MAXNS]; /* address of name server */
138#define nsaddr nsaddr_list[0] /* for backward compatibility */
139 unsigned short id; /* current message id */
140 char *dnsrch[MAXDNSRCH+1]; /* components of domain to search */
141 char defdname[256]; /* default domain (deprecated) */
142 unsigned int pfcode; /* RES_PRF_ flags - see below. */
143 unsigned ndots:4; /* threshold for initial abs. query */
144 unsigned nsort:4; /* number of elements in sort_list[] */
145 char unused[3];
146 struct {
147 struct in_addr addr;
148 u_int32_t mask;
149 } sort_list[MAXRESOLVSORT];
150 char lookups[MAXDNSLUS];
151 struct { time_t __res_sec; long __res_nsec; } restimespec;
152 time_t reschktime;
153};
154
155#if 1 /* INET6 */
156/*
157 * replacement of __res_state, separated to keep binary compatibility.
158 */
159struct __res_state_ext {
160 struct sockaddr_storage nsaddr_list[MAXNS];
161 struct {
162 int af; /* address family for addr, mask */
163 union {
164 struct in_addr ina;
165 struct in6_addr in6a;
166 } addr, mask;
167 } sort_list[MAXRESOLVSORT];
168};
169#endif
170
171
172/*
173 * Resolver options (keep these in synch with res_debug.c, please)
174 */
175#define RES_INIT 0x00000001 /* address initialized */
176#define RES_DEBUG 0x00000002 /* print debug messages */
177#define RES_AAONLY 0x00000004 /* authoritative answers only (!IMPL)*/
178#define RES_USEVC 0x00000008 /* use virtual circuit */
179#define RES_PRIMARY 0x00000010 /* query primary server only (!IMPL) */
180#define RES_IGNTC 0x00000020 /* ignore trucation errors */
181#define RES_RECURSE 0x00000040 /* recursion desired */
182#define RES_DEFNAMES 0x00000080 /* use default domain name */
183#define RES_STAYOPEN 0x00000100 /* Keep TCP socket open */
184#define RES_DNSRCH 0x00000200 /* search up local domain tree */
185#define RES_INSECURE1 0x00000400 /* type 1 security disabled */
186#define RES_INSECURE2 0x00000800 /* type 2 security disabled */
187#define RES_NOALIASES 0x00001000 /* shuts off HOSTALIASES feature */
188#define RES_USE_INET6 0x00002000 /* use/map IPv6 in gethostbyname() */
189/* KAME extensions: use higher bit to avoid conflict with ISC use */
190#define RES_USE_EDNS0 0x40000000 /* use EDNS0 */
191/* DNSSEC extensions: use higher bit to avoid conflict with ISC use */
192#define RES_USE_DNSSEC 0x20000000 /* use DNSSEC using OK bit in OPT */
193#define RES_USE_CD 0x10000000 /* set Checking Disabled flag */
194#define RES_TRUSTAD 0x80000000 /* Request AD, keep it in responses. */
195
196#define RES_DEFAULT (RES_RECURSE | RES_DEFNAMES | RES_DNSRCH)
197
198/*
199 * Resolver "pfcode" values. Used by dig.
200 */
201#define RES_PRF_STATS 0x00000001
202/* 0x00000002 */
203#define RES_PRF_CLASS 0x00000004
204#define RES_PRF_CMD 0x00000008
205#define RES_PRF_QUES 0x00000010
206#define RES_PRF_ANS 0x00000020
207#define RES_PRF_AUTH 0x00000040
208#define RES_PRF_ADD 0x00000080
209#define RES_PRF_HEAD1 0x00000100
210#define RES_PRF_HEAD2 0x00000200
211#define RES_PRF_TTLID 0x00000400
212#define RES_PRF_HEADX 0x00000800
213#define RES_PRF_QUERY 0x00001000
214#define RES_PRF_REPLY 0x00002000
215#define RES_PRF_INIT 0x00004000
216/* 0x00008000 */
217
218/* hooks are still experimental as of 4.9.2 */
219typedef enum { res_goahead, res_nextns, res_modified, res_done, res_error }
220 res_sendhookact;
221
222typedef res_sendhookact (*res_send_qhook)(struct sockaddr_in * const *ns,
223 const unsigned char **query,
224 int *querylen,
225 unsigned char *ans,
226 int anssiz,
227 int *resplen);
228
229typedef res_sendhookact (*res_send_rhook)(const struct sockaddr_in *ns,
230 const unsigned char *query,
231 int querylen,
232 unsigned char *ans,
233 int anssiz,
234 int *resplen);
235
236struct res_sym {
237 int number; /* Identifying number, like T_MX */
238 char * name; /* Its symbolic name, like "MX" */
239 char * humanname; /* Its fun name, like "mail exchanger" */
240};
241
242extern struct __res_state _res;
243#if 1 /* INET6 */
244extern struct __res_state_ext _res_ext;
245#endif
246extern const struct res_sym __p_class_syms[];
247extern const struct res_sym __p_type_syms[];
248
249/* Private routines shared between libc/net, named, nslookup and others. */
250#define res_hnok __res_hnok
251#define res_ownok __res_ownok
252#define res_mailok __res_mailok
253#define res_dnok __res_dnok
254#define sym_ntos __sym_ntos
255#define b64_ntop __b64_ntop
256#define b64_pton __b64_pton
257#define dn_skipname __dn_skipname
258#define putlong __putlong
259#define putshort __putshort
260#define p_class __p_class
261#define p_type __p_type
262#define dn_count_labels __dn_count_labels
263#define dn_comp __dn_comp
264#define res_randomid __res_randomid
265#define res_send __res_send
266#define res_opt __res_opt
267
268#ifdef BIND_RES_POSIX3
269#define dn_expand __dn_expand
270#define res_init __res_init
271#define res_query __res_query
272#define res_search __res_search
273#define res_querydomain __res_querydomain
274#define res_mkquery __res_mkquery
275#endif
276
277__BEGIN_DECLS
278int res_hnok(const char *);
279int res_ownok(const char *);
280int res_mailok(const char *);
281int res_dnok(const char *);
282const char * sym_ntos(const struct res_sym *, int, int *);
283int b64_ntop(unsigned char const *, size_t, char *, size_t);
284int b64_pton(char const *, unsigned char *, size_t);
285int dn_skipname(const unsigned char *,
286 const unsigned char *);
287void putlong(u_int32_t, unsigned char *);
288void putshort(u_int16_t, unsigned char *);
289const char * p_class(int);
290const char * p_type(int);
291int dn_comp(const char *, unsigned char *, int,
292 unsigned char **, unsigned char **);
293int dn_expand(const unsigned char *, const unsigned char *,
294 const unsigned char *, char *, int);
295int res_init(void);
296unsigned int res_randomid(void);
297int res_query(const char *, int, int, unsigned char *, int)
298 __attribute__((__bounded__(__string__,4,5)));
299int res_search(const char *, int, int, unsigned char *, int)
300 __attribute__((__bounded__(__string__,4,5)));
301int res_querydomain(const char *, const char *, int, int,
302 unsigned char *, int)
303 __attribute__((__bounded__(__string__,5,6)));
304int res_mkquery(int, const char *, int, int,
305 const unsigned char *, int, const unsigned char *,
306 unsigned char *, int)
307 __attribute__((__bounded__(__string__,5,6)))
308 __attribute__((__bounded__(__string__,8,9)));
309int res_send(const unsigned char *, int, unsigned char *,
310 int)
311 __attribute__((__bounded__(__string__,3,4)));
312__END_DECLS
313
314#endif /* !_RESOLV_H_ */