1/*-
2 * SPDX-License-Identifier: (ISC AND BSD-3-Clause)
3 *
4 * Portions Copyright (C) 2004, 2005, 2008, 2009  Internet Systems Consortium, Inc. ("ISC")
5 * Portions Copyright (C) 1995-2003  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) 1983, 1987, 1989
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 *	$Id: resolv.h,v 1.30 2009/03/03 01:52:48 each Exp $
51 */
52
53#ifndef _RESOLV_H_
54#define	_RESOLV_H_
55
56#include <sys/param.h>
57#include <sys/types.h>
58#include <sys/cdefs.h>
59#include <sys/socket.h>
60#include <stdio.h>
61#include <netinet/in.h>
62#include <arpa/nameser.h>
63
64/*%
65 * Revision information.  This is the release date in YYYYMMDD format.
66 * It can change every day so the right thing to do with it is use it
67 * in preprocessor commands such as "#if (__RES > 19931104)".  Do not
68 * compare for equality; rather, use it to determine whether your resolver
69 * is new enough to contain a certain feature.
70 */
71
72#define	__RES	20090302
73
74/*%
75 * This used to be defined in res_query.c, now it's in herror.c.
76 * [XXX no it's not.  It's in irs/irs_data.c]
77 * It was
78 * never extern'd by any *.h file before it was placed here.  For thread
79 * aware programs, the last h_errno value set is stored in res->h_errno.
80 *
81 * XXX:	There doesn't seem to be a good reason for exposing RES_SET_H_ERRNO
82 *	(and __h_errno_set) to the public via <resolv.h>.
83 * XXX:	__h_errno_set is really part of IRS, not part of the resolver.
84 *	If somebody wants to build and use a resolver that doesn't use IRS,
85 *	what do they do?  Perhaps something like
86 *		#ifdef WANT_IRS
87 *		# define RES_SET_H_ERRNO(r,x) __h_errno_set(r,x)
88 *		#else
89 *		# define RES_SET_H_ERRNO(r,x) (h_errno = (r)->res_h_errno = (x))
90 *		#endif
91 */
92
93#define RES_SET_H_ERRNO(r,x) __h_errno_set(r,x)
94struct __res_state; /*%< forward */
95__BEGIN_DECLS
96void __h_errno_set(struct __res_state *, int);
97__END_DECLS
98
99/*%
100 * Resolver configuration file.
101 * Normally not present, but may contain the address of the
102 * initial name server(s) to query and the domain search list.
103 */
104
105#ifndef _PATH_RESCONF
106#define	_PATH_RESCONF        "/etc/resolv.conf"
107#endif
108
109typedef enum { res_goahead, res_nextns, res_modified, res_done, res_error }
110	res_sendhookact;
111
112typedef res_sendhookact (*res_send_qhook)(struct sockaddr * const *,
113					  const u_char **, int *,
114					  u_char *, int, int *);
115
116typedef res_sendhookact (*res_send_rhook)(const struct sockaddr *,
117					  const u_char *, int, u_char *,
118					  int, int *);
119
120struct res_sym {
121	int		number;	   /*%< Identifying number, like T_MX */
122	const char *	name;	   /*%< Its symbolic name, like "MX" */
123	const char *	humanname; /*%< Its fun name, like "mail exchanger" */
124};
125
126/*%
127 * Global defines and variables for resolver stub.
128 */
129#define	MAXNS			3	/*%< max # name servers we'll track */
130#define	MAXDFLSRCH		3	/*%< # default domain levels to try */
131#define	MAXDNSRCH		6	/*%< max # domains in search path */
132#define	LOCALDOMAINPARTS	2	/*%< min levels in name that is "local" */
133#define	RES_TIMEOUT		5	/*%< min. seconds between retries */
134#define	MAXRESOLVSORT		10	/*%< number of net to sort on */
135#define	RES_MAXNDOTS		15	/*%< should reflect bit field size */
136#define	RES_MAXRETRANS		30	/*%< only for resolv.conf/RES_OPTIONS */
137#define	RES_MAXRETRY		5	/*%< only for resolv.conf/RES_OPTIONS */
138#define	RES_DFLRETRY		2	/*%< Default #/tries. */
139#define	RES_MAXTIME		65535	/*%< Infinity, in milliseconds. */
140struct __res_state_ext;
141
142struct __res_state {
143	int	retrans;	 	/*%< retransmission time interval */
144	int	retry;			/*%< number of times to retransmit */
145	/*
146	 * XXX: If `sun' is defined, `options' and `pfcode' are
147	 * defined as u_int in original BIND9 distribution.  However,
148	 * it breaks binary backward compatibility against FreeBSD's
149	 * resolver.  So, we changed not to see `sun'.
150	 */
151#if defined(sun) && 0
152	u_int	options;		/*%< option flags - see below. */
153#else
154	u_long	options;		/*%< option flags - see below. */
155#endif
156	int	nscount;		/*%< number of name servers */
157	struct sockaddr_in
158		nsaddr_list[MAXNS];	/*%< address of name server */
159#define	nsaddr	nsaddr_list[0]		/*%< for backward compatibility */
160	u_short	id;			/*%< current message id */
161	char	*dnsrch[MAXDNSRCH+1];	/*%< components of domain to search */
162	char	defdname[256];		/*%< default domain (deprecated) */
163#if defined(sun) && 0
164	u_int	pfcode;			/*%< RES_PRF_ flags - see below. */
165#else
166	u_long	pfcode;			/*%< RES_PRF_ flags - see below. */
167#endif
168	unsigned ndots:4;		/*%< threshold for initial abs. query */
169	unsigned nsort:4;		/*%< number of elements in sort_list[] */
170	char	unused[3];
171	struct {
172		struct in_addr	addr;
173		u_int32_t	mask;
174	} sort_list[MAXRESOLVSORT];
175	res_send_qhook qhook;		/*%< query hook */
176	res_send_rhook rhook;		/*%< response hook */
177	int	res_h_errno;		/*%< last one set for this context */
178	int	_vcsock;		/*%< PRIVATE: for res_send VC i/o */
179	u_int	_flags;			/*%< PRIVATE: see below */
180	u_int	_pad;			/*%< make _u 64 bit aligned */
181	union {
182		/* On an 32-bit arch this means 512b total. */
183		char	pad[72 - 4*sizeof (int) - 3*sizeof (void *)];
184		struct {
185			u_int16_t		nscount;
186			u_int16_t		nstimes[MAXNS];	/*%< ms. */
187			int			nssocks[MAXNS];
188			struct __res_state_ext *ext;	/*%< extension for IPv6 */
189		} _ext;
190	} _u;
191	u_char	*_rnd;			/*%< PRIVATE: random state */
192};
193
194typedef struct __res_state *res_state;
195
196union res_sockaddr_union {
197	struct sockaddr_in	sin;
198#ifdef IN6ADDR_ANY_INIT
199	struct sockaddr_in6	sin6;
200#endif
201#ifdef ISC_ALIGN64
202	int64_t			__align64;	/*%< 64bit alignment */
203#else
204	int32_t			__align32;	/*%< 32bit alignment */
205#endif
206	char			__space[128];   /*%< max size */
207};
208
209/*%
210 * Resolver flags (used to be discrete per-module statics ints).
211 */
212#define	RES_F_VC	0x00000001	/*%< socket is TCP */
213#define	RES_F_CONN	0x00000002	/*%< socket is connected */
214#define	RES_F_EDNS0ERR	0x00000004	/*%< EDNS0 caused errors */
215#define	RES_F__UNUSED	0x00000008	/*%< (unused) */
216#define	RES_F_LASTMASK	0x000000F0	/*%< ordinal server of last res_nsend */
217#define	RES_F_LASTSHIFT	4		/*%< bit position of LASTMASK "flag" */
218#define	RES_GETLAST(res) (((res)._flags & RES_F_LASTMASK) >> RES_F_LASTSHIFT)
219
220/* res_findzonecut2() options */
221#define	RES_EXHAUSTIVE	0x00000001	/*%< always do all queries */
222#define	RES_IPV4ONLY	0x00000002	/*%< IPv4 only */
223#define	RES_IPV6ONLY	0x00000004	/*%< IPv6 only */
224
225/*%
226 * Resolver options (keep these in synch with res_debug.c, please)
227 */
228#define RES_INIT	0x00000001	/*%< address initialized */
229#define RES_DEBUG	0x00000002	/*%< print debug messages */
230#define RES_AAONLY	0x00000004	/*%< authoritative answers only (!IMPL)*/
231#define RES_USEVC	0x00000008	/*%< use virtual circuit */
232#define RES_PRIMARY	0x00000010	/*%< query primary server only (!IMPL) */
233#define RES_IGNTC	0x00000020	/*%< ignore truncation errors */
234#define RES_RECURSE	0x00000040	/*%< recursion desired */
235#define RES_DEFNAMES	0x00000080	/*%< use default domain name */
236#define RES_STAYOPEN	0x00000100	/*%< Keep TCP socket open */
237#define RES_DNSRCH	0x00000200	/*%< search up local domain tree */
238#define	RES_INSECURE1	0x00000400	/*%< type 1 security disabled */
239#define	RES_INSECURE2	0x00000800	/*%< type 2 security disabled */
240#define	RES_NOALIASES	0x00001000	/*%< shuts off HOSTALIASES feature */
241#define	RES_USE_INET6	0x00002000	/*%< use/map IPv6 in gethostbyname() */
242#define RES_ROTATE	0x00004000	/*%< rotate ns list after each query */
243#define	RES_NOCHECKNAME	0x00008000	/*%< do not check names for sanity. */
244#define	RES_KEEPTSIG	0x00010000	/*%< do not strip TSIG records */
245#define	RES_BLAST	0x00020000	/*%< blast all recursive servers */
246#define RES_NSID	0x00040000      /*%< request name server ID */
247#define RES_NOTLDQUERY	0x00100000	/*%< don't unqualified name as a tld */
248#define RES_USE_DNSSEC	0x00200000	/*%< use DNSSEC using OK bit in OPT */
249/* #define RES_DEBUG2	0x00400000 */	/* nslookup internal */
250/* KAME extensions: use higher bit to avoid conflict with ISC use */
251#define RES_USE_DNAME	0x10000000	/*%< use DNAME */
252#define RES_USE_EDNS0	0x40000000	/*%< use EDNS0 if configured */
253#define RES_NO_NIBBLE2	0x80000000	/*%< disable alternate nibble lookup */
254
255#define RES_DEFAULT	(RES_RECURSE | RES_DEFNAMES | \
256			 RES_DNSRCH | RES_NO_NIBBLE2)
257
258/*%
259 * Resolver "pfcode" values.  Used by dig.
260 */
261#define	RES_PRF_STATS	0x00000001
262#define	RES_PRF_UPDATE	0x00000002
263#define	RES_PRF_CLASS   0x00000004
264#define	RES_PRF_CMD	0x00000008
265#define	RES_PRF_QUES	0x00000010
266#define	RES_PRF_ANS	0x00000020
267#define	RES_PRF_AUTH	0x00000040
268#define	RES_PRF_ADD	0x00000080
269#define	RES_PRF_HEAD1	0x00000100
270#define	RES_PRF_HEAD2	0x00000200
271#define	RES_PRF_TTLID	0x00000400
272#define	RES_PRF_HEADX	0x00000800
273#define	RES_PRF_QUERY	0x00001000
274#define	RES_PRF_REPLY	0x00002000
275#define	RES_PRF_INIT	0x00004000
276#define	RES_PRF_TRUNC	0x00008000
277/*			0x00010000	*/
278
279/* Things involving an internal (static) resolver context. */
280__BEGIN_DECLS
281extern struct __res_state *__res_state(void);
282__END_DECLS
283#define _res (*__res_state())
284
285#ifndef __BIND_NOSTATIC
286#define fp_nquery		__fp_nquery
287#define fp_query		__fp_query
288#define hostalias		__hostalias
289#define p_query			__p_query
290#define res_close		__res_close
291#define res_init		__res_init
292#define res_isourserver		__res_isourserver
293#define res_mkquery		__res_mkquery
294#define res_opt			__res_opt
295#define res_query		__res_query
296#define res_querydomain		__res_querydomain
297#define res_search		__res_search
298#define res_send		__res_send
299#define res_sendsigned		__res_sendsigned
300
301__BEGIN_DECLS
302void		fp_nquery(const u_char *, int, FILE *);
303void		fp_query(const u_char *, FILE *);
304const char *	hostalias(const char *);
305void		p_query(const u_char *);
306void		res_close(void);
307int		res_init(void);
308int		res_isourserver(const struct sockaddr_in *);
309int		res_mkquery(int, const char *, int, int, const u_char *,
310				 int, const u_char *, u_char *, int);
311int		res_opt(int, u_char *, int, int);
312int		res_query(const char *, int, int, u_char *, int);
313int		res_querydomain(const char *, const char *, int, int,
314				     u_char *, int);
315int		res_search(const char *, int, int, u_char *, int);
316int		res_send(const u_char *, int, u_char *, int);
317int		res_sendsigned(const u_char *, int, ns_tsig_key *,
318				    u_char *, int);
319__END_DECLS
320#endif
321
322#if !defined(SHARED_LIBBIND) || defined(LIB)
323/*
324 * If libbind is a shared object (well, DLL anyway)
325 * these externs break the linker when resolv.h is
326 * included by a lib client (like named)
327 * Make them go away if a client is including this
328 *
329 */
330extern const struct res_sym __p_key_syms[];
331extern const struct res_sym __p_cert_syms[];
332extern const struct res_sym __p_class_syms[];
333extern const struct res_sym __p_type_syms[];
334extern const struct res_sym __p_rcode_syms[];
335#endif /* SHARED_LIBBIND */
336
337#define b64_ntop		__b64_ntop
338#define b64_pton		__b64_pton
339#define dn_comp			__dn_comp
340#define dn_count_labels		__dn_count_labels
341#define dn_expand		__dn_expand
342#define dn_skipname		__dn_skipname
343#define fp_resstat		__fp_resstat
344#define loc_aton		__loc_aton
345#define loc_ntoa		__loc_ntoa
346#define p_cdname		__p_cdname
347#define p_cdnname		__p_cdnname
348#define p_class			__p_class
349#define p_fqname		__p_fqname
350#define p_fqnname		__p_fqnname
351#define p_option		__p_option
352#define p_secstodate		__p_secstodate
353#define p_section		__p_section
354#define p_time			__p_time
355#define p_type			__p_type
356#define p_rcode			__p_rcode
357#define p_sockun		__p_sockun
358#define putlong			__putlong
359#define putshort		__putshort
360#define res_dnok		__res_dnok
361#if 0
362#define res_findzonecut		__res_findzonecut
363#endif
364#define res_findzonecut2	__res_findzonecut2
365#define res_hnok		__res_hnok
366#define res_hostalias		__res_hostalias
367#define res_mailok		__res_mailok
368#define res_nameinquery		__res_nameinquery
369#define res_nclose		__res_nclose
370#define res_ninit		__res_ninit
371#define res_nmkquery		__res_nmkquery
372#define res_pquery		__res_pquery
373#define res_nquery		__res_nquery
374#define res_nquerydomain	__res_nquerydomain
375#define res_nsearch		__res_nsearch
376#define res_nsend		__res_nsend
377#if 0
378#define res_nsendsigned		__res_nsendsigned
379#endif
380#define res_nisourserver	__res_nisourserver
381#define res_ownok		__res_ownok
382#define res_queriesmatch	__res_queriesmatch
383#define res_rndinit		__res_rndinit
384#define res_randomid		__res_randomid
385#define res_nrandomid		__res_nrandomid
386#define sym_ntop		__sym_ntop
387#define sym_ntos		__sym_ntos
388#define sym_ston		__sym_ston
389#define res_nopt		__res_nopt
390#define res_nopt_rdata       	__res_nopt_rdata
391#define res_ndestroy		__res_ndestroy
392#define	res_nametoclass		__res_nametoclass
393#define	res_nametotype		__res_nametotype
394#define	res_setservers		__res_setservers
395#define	res_getservers		__res_getservers
396#if 0
397#define	res_buildprotolist	__res_buildprotolist
398#define	res_destroyprotolist	__res_destroyprotolist
399#define	res_destroyservicelist	__res_destroyservicelist
400#define	res_get_nibblesuffix	__res_get_nibblesuffix
401#define	res_get_nibblesuffix2	__res_get_nibblesuffix2
402#endif
403#define	res_ourserver_p		__res_ourserver_p
404#if 0
405#define	res_protocolname	__res_protocolname
406#define	res_protocolnumber	__res_protocolnumber
407#endif
408#define	res_send_setqhook	__res_send_setqhook
409#define	res_send_setrhook	__res_send_setrhook
410#if 0
411#define	res_servicename		__res_servicename
412#define	res_servicenumber	__res_servicenumber
413#endif
414__BEGIN_DECLS
415int		res_hnok(const char *);
416int		res_ownok(const char *);
417int		res_mailok(const char *);
418int		res_dnok(const char *);
419int		sym_ston(const struct res_sym *, const char *, int *);
420const char *	sym_ntos(const struct res_sym *, int, int *);
421const char *	sym_ntop(const struct res_sym *, int, int *);
422int		b64_ntop(u_char const *, size_t, char *, size_t);
423int		b64_pton(char const *, u_char *, size_t);
424int		loc_aton(const char *, u_char *);
425const char *	loc_ntoa(const u_char *, char *);
426int		dn_skipname(const u_char *, const u_char *);
427void		putlong(u_int32_t, u_char *);
428void		putshort(u_int16_t, u_char *);
429#ifndef __ultrix__
430u_int16_t	_getshort(const u_char *);
431u_int32_t	_getlong(const u_char *);
432#endif
433const char *	p_class(int);
434const char *	p_time(u_int32_t);
435const char *	p_type(int);
436const char *	p_rcode(int);
437const char *	p_sockun(union res_sockaddr_union, char *, size_t);
438const u_char *	p_cdnname(const u_char *, const u_char *, int, FILE *);
439const u_char *	p_cdname(const u_char *, const u_char *, FILE *);
440const u_char *	p_fqnname(const u_char *, const u_char *, int, char *, int);
441const u_char *	p_fqname(const u_char *, const u_char *, FILE *);
442const char *	p_option(u_long);
443char *		p_secstodate(u_long);
444int		dn_count_labels(const char *);
445int		dn_comp(const char *, u_char *, int, u_char **, u_char **);
446int		dn_expand(const u_char *, const u_char *, const u_char *,
447			  char *, int);
448void		res_rndinit(res_state);
449u_int		res_randomid(void);
450u_int		res_nrandomid(res_state);
451int		res_nameinquery(const char *, int, int, const u_char *,
452				const u_char *);
453int		res_queriesmatch(const u_char *, const u_char *,
454				 const u_char *, const u_char *);
455const char *	p_section(int, int);
456/* Things involving a resolver context. */
457int		res_ninit(res_state);
458int		res_nisourserver(const res_state, const struct sockaddr_in *);
459void		fp_resstat(const res_state, FILE *);
460void		res_pquery(const res_state, const u_char *, int, FILE *);
461const char *	res_hostalias(const res_state, const char *, char *, size_t);
462int		res_nquery(res_state, const char *, int, int, u_char *, int);
463int		res_nsearch(res_state, const char *, int, int, u_char *, int);
464int		res_nquerydomain(res_state, const char *, const char *,
465				 int, int, u_char *, int);
466int		res_nmkquery(res_state, int, const char *, int, int,
467			     const u_char *, int, const u_char *,
468			     u_char *, int);
469int		res_nsend(res_state, const u_char *, int, u_char *, int);
470#if 0
471int		res_nsendsigned(res_state, const u_char *, int,
472				ns_tsig_key *, u_char *, int);
473int		res_findzonecut(res_state, const char *, ns_class, int,
474				char *, size_t, struct in_addr *, int);
475#endif
476int		res_findzonecut2(res_state, const char *, ns_class, int,
477				 char *, size_t,
478				 union res_sockaddr_union *, int);
479void		res_nclose(res_state);
480int		res_nopt(res_state, int, u_char *, int, int);
481int		res_nopt_rdata(res_state, int, u_char *, int, u_char *,
482			       u_short, u_short, u_char *);
483void		res_send_setqhook(res_send_qhook);
484void		res_send_setrhook(res_send_rhook);
485int		__res_vinit(res_state, int);
486#if 0
487void		res_destroyservicelist(void);
488const char *	res_servicename(u_int16_t, const char *);
489const char *	res_protocolname(int);
490void		res_destroyprotolist(void);
491void		res_buildprotolist(void);
492const char *	res_get_nibblesuffix(res_state);
493const char *	res_get_nibblesuffix2(res_state);
494#endif
495void		res_ndestroy(res_state);
496u_int16_t	res_nametoclass(const char *, int *);
497u_int16_t	res_nametotype(const char *, int *);
498void		res_setservers(res_state, const union res_sockaddr_union *,
499			       int);
500int		res_getservers(res_state, union res_sockaddr_union *, int);
501__END_DECLS
502
503#endif /* !_RESOLV_H_ */
504/*! \file */
505