Asterisk - The Open Source Telephony Project GIT-master-0bf3178
dns.h
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1/*
2 * Asterisk -- An open source telephony toolkit.
3 *
4 * Written by Thorsten Lockert <tholo@trollphone.org>
5 *
6 * Funding provided by Troll Phone Networks AS
7 *
8 * See http://www.asterisk.org for more information about
9 * the Asterisk project. Please do not directly contact
10 * any of the maintainers of this project for assistance;
11 * the project provides a web site, mailing lists and IRC
12 * channels for your use.
13 *
14 * This program is free software, distributed under the terms of
15 * the GNU General Public License Version 2. See the LICENSE file
16 * at the top of the source tree.
17 */
18
19/*! \file
20 * \brief DNS support for Asterisk
21 * \author Thorsten Lockert <tholo@trollphone.org>
22 */
23
24#ifndef _ASTERISK_DNS_H
25#define _ASTERISK_DNS_H
26
27/*! \brief DNS search return values */
29 AST_DNS_SEARCH_FAILURE = -1, /*!< DNS search resulted in failure */
30 AST_DNS_SEARCH_NO_RECORDS = 0, /*!< DNS search yielded no results */
31 AST_DNS_SEARCH_SUCCESS = 1 /*!< DNS search yielded at least one discovered record */
32};
33
34/*!
35 * \brief Perform DNS lookup (used by DNS, enum and SRV lookups)
36 *
37 * \param context Void pointer containing data to use in the callback function.
38 * \param dname Domain name to lookup (host, SRV domain, TXT record name).
39 * \param class Record Class (see "man res_search").
40 * \param type Record type (see "man res_search").
41 * \param callback Callback function for handling the discovered resource records from
42 * the DNS search. len gets the length of the full DNS response.
43 *
44 * \retval -1 on search failure
45 * \retval 0 on no records found
46 * \retval 1 on success
47 *
48 * \note Asterisk DNS is synchronus at this time. This means that if your DNS
49 * service does not work, Asterisk may lock while waiting for a response.
50 */
51int ast_search_dns(void *context, const char *dname, int class, int type,
52 int (*callback)(void *context, unsigned char *answer, int len, unsigned char *fullanswer));
53
54/*!
55 * \brief Extended version of the DNS search function.
56 *
57 * \details Performs a DNS lookup, (used by DNS, enum and SRV lookups), parses the
58 * results and notifies the observer with the response and discovered records
59 * via invoking the provided callbacks (used by ast_dns_system_resolver).
60 *
61 * \param context Void pointer containing data to use in the handler functions.
62 * \param dname Domain name to lookup (host, SRV domain, TXT record name).
63 * \param rr_class Record Class (see "man res_search").
64 * \param rr_type Record type (see "man res_search").
65 * \param response_handler Callback function for handling the DNS response. Invoked upon
66 * completion of the DNS search.
67 * \param record_handler Callback function for handling the discovered resource
68 * records from the DNS search. Invoked n times, where n is the
69 * number of records discovered while parsing the DNS
70 * response.
71 *
72 * \retval AST_DNS_SEARCH_FAILURE on search failure
73 * \retval AST_DNS_SEARCH_NO_RECORDS on no records found
74 * \retval AST_DNS_SEARCH_SUCCESS on success
75 *
76 * \note Asterisk DNS is synchronus at this time. This means that if your DNS
77 * service does not work, Asterisk may lock while waiting for a response.
78 */
79enum ast_dns_search_result ast_search_dns_ex(void *context, const char *dname, int rr_class, int rr_type,
80 int (*response_handler)(void *context, unsigned char *dns_response, int dns_response_len, int rcode),
81 int (*record_handler)(void *context, unsigned char *record, int record_len, int ttl));
82
83/*! \brief Retrieve the configured nameservers of the system */
85
86#endif /* _ASTERISK_DNS_H */
static const char type[]
Definition: chan_ooh323.c:109
static int answer(void *data)
Definition: chan_pjsip.c:687
enum ast_dns_search_result ast_search_dns_ex(void *context, const char *dname, int rr_class, int rr_type, int(*response_handler)(void *context, unsigned char *dns_response, int dns_response_len, int rcode), int(*record_handler)(void *context, unsigned char *record, int record_len, int ttl))
Extended version of the DNS search function.
Definition: dns.c:536
struct ao2_container * ast_dns_get_nameservers(void)
Retrieve the configured nameservers of the system.
Definition: dns.c:581
int ast_search_dns(void *context, const char *dname, int class, int type, int(*callback)(void *context, unsigned char *answer, int len, unsigned char *fullanswer))
Perform DNS lookup (used by DNS, enum and SRV lookups)
Definition: dns.c:491
ast_dns_search_result
DNS search return values.
Definition: dns.h:28
@ AST_DNS_SEARCH_SUCCESS
Definition: dns.h:31
@ AST_DNS_SEARCH_FAILURE
Definition: dns.h:29
@ AST_DNS_SEARCH_NO_RECORDS
Definition: dns.h:30
static int len(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t buflen)
Generic container type.