1/*	$OpenBSD: asr.h,v 1.2 2019/10/24 05:57:41 otto Exp $	*/
2/*
3 * Copyright (c) 2012-2014 Eric Faurot <eric@openbsd.org>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18/*
19 * Expected fd conditions
20 */
21#define ASR_WANT_READ	1
22#define ASR_WANT_WRITE	2
23
24/*
25 * Structure through which asynchronous query results are returned when
26 * calling asr_run().
27 */
28struct asr_result {
29	/* Fields set if the query is not done yet (asr_run returns 0) */
30	int	 ar_cond;	/* ASR_WANT_READ or ASR_WANT_WRITE */
31	int	 ar_fd;		/* the fd waiting for io condition */
32	int	 ar_timeout;	/* time to wait for in milliseconds */
33
34	/* Error fields.  Depends on the query type. */
35	int	 ar_errno;
36	int	 ar_h_errno;
37	int	 ar_gai_errno;
38	int	 ar_rrset_errno;
39
40	/* Result for res_*_async() calls */
41	int	 ar_count;	/* number of answers in the dns reply */
42	int	 ar_rcode;	/* response code in the dns reply */
43	void	*ar_data;	/* raw reply packet (must be freed) */
44	int	 ar_datalen;	/* reply packet length */
45	struct sockaddr_storage ar_ns; /* nameserver that responded */
46
47	/* Result for other calls. Must be freed properly. */
48	struct addrinfo	 *ar_addrinfo;
49	struct rrsetinfo *ar_rrsetinfo;
50	struct hostent	 *ar_hostent;
51	struct netent	 *ar_netent;
52};
53
54/*
55 * Asynchronous query management.
56 */
57
58/* Forward declaration. The API uses opaque pointers as query handles. */
59struct asr_query;
60
61void *asr_resolver_from_string(const char *);
62void asr_resolver_free(void *);
63int asr_run(struct asr_query *, struct asr_result *);
64int asr_run_sync(struct asr_query *, struct asr_result *);
65void asr_abort(struct asr_query *);
66
67/*
68 * Asynchronous version of the resolver functions. Similar prototypes, with
69 * an extra context parameter at the end which must currently be set to NULL.
70 * All functions return a handle suitable for use with the management functions
71 * above.
72 */
73struct asr_query *res_send_async(const unsigned char *, int, void *);
74struct asr_query *res_query_async(const char *, int, int, void *);
75struct asr_query *res_search_async(const char *, int, int, void *);
76
77struct asr_query *getrrsetbyname_async(const char *, unsigned int, unsigned int,
78    unsigned int, void *);
79
80struct asr_query *gethostbyname_async(const char *, void *);
81struct asr_query *gethostbyname2_async(const char *, int, void *);
82struct asr_query *gethostbyaddr_async(const void *, socklen_t, int, void *);
83
84struct asr_query *getnetbyname_async(const char *, void *);
85struct asr_query *getnetbyaddr_async(in_addr_t, int, void *);
86
87struct asr_query *getaddrinfo_async(const char *, const char *,
88    const struct addrinfo *, void *);
89struct asr_query *getnameinfo_async(const struct sockaddr *, socklen_t, char *,
90    size_t, char *, size_t, int, void *);
91