/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
#ifndef DNS_BYADDR_H
#define DNS_BYADDR_H 1
/*****
***** Module Info
*****/
/*! \file dns/byaddr.h
* \brief
* The byaddr module provides reverse lookup services for IPv4 and IPv6
* addresses.
*
* MP:
*\li The module ensures appropriate synchronization of data structures it
* creates and manipulates.
*
* Reliability:
*\li No anticipated impact.
*
* Resources:
*\li TBS
*
* Security:
*\li No anticipated impact.
*
* Standards:
*\li RFCs: 1034, 1035, 2181, TBS
*\li Drafts: TBS
*/
#include <isc/event.h>
#include <isc/lang.h>
#include <dns/types.h>
ISC_LANG_BEGINDECLS
/*%
* A 'dns_byaddrevent_t' is returned when a byaddr completes.
* The sender field will be set to the byaddr that completed. If 'result'
* is ISC_R_SUCCESS, then 'names' will contain a list of names associated
* with the address. The recipient of the event must not change the list
* and must not refer to any of the name data after the event is freed.
*/
typedef struct dns_byaddrevent {
ISC_EVENT_COMMON(struct dns_byaddrevent);
isc_result_t result;
dns_namelist_t names;
} dns_byaddrevent_t;
isc_result_t
dns_byaddr_create(isc_mem_t *mctx, const isc_netaddr_t *address,
dns_view_t *view, unsigned int options, isc_task_t *task,
isc_taskaction_t action, void *arg, dns_byaddr_t **byaddrp);
/*%<
* Find the domain name of 'address'.
*
* Notes:
*
*\li There is a reverse lookup format for IPv6 addresses, 'nibble'
*
*\li The 'nibble' format for that address is
*
* \code
* 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.e.f.ip6.arpa.
* \endcode
*
* Requires:
*
*\li 'mctx' is a valid mctx.
*
*\li 'address' is a valid IPv4 or IPv6 address.
*
*\li 'view' is a valid view which has a resolver.
*
*\li 'task' is a valid task.
*
*\li byaddrp != NULL && *byaddrp == NULL
*
* Returns:
*
*\li #ISC_R_SUCCESS
*\li #ISC_R_NOMEMORY
*
*\li Any resolver-related error (e.g. #ISC_R_SHUTTINGDOWN) may also be
* returned.
*/
void
dns_byaddr_cancel(dns_byaddr_t *byaddr);
/*%<
* Cancel 'byaddr'.
*
* Notes:
*
*\li If 'byaddr' has not completed, post its #DNS_EVENT_BYADDRDONE
* event with a result code of #ISC_R_CANCELED.
*
* Requires:
*
*\li 'byaddr' is a valid byaddr.
*/
void
dns_byaddr_destroy(dns_byaddr_t **byaddrp);
/*%<
* Destroy 'byaddr'.
*
* Requires:
*
*\li '*byaddrp' is a valid byaddr.
*
*\li The caller has received the #DNS_EVENT_BYADDRDONE event (either because
* the byaddr completed or because dns_byaddr_cancel() was called).
*
* Ensures:
*
*\li *byaddrp == NULL.
*/
isc_result_t
dns_byaddr_createptrname(const isc_netaddr_t *address, unsigned int options,
dns_name_t *name);
/*%<
* Creates a name that would be used in a PTR query for this address. The
* nibble flag indicates that the 'nibble' format is to be used if an IPv6
* address is provided, instead of the 'bitstring' format. Since we dropped
* the support of the bitstring labels, it is expected that the flag is always
* set. 'options' are the same as for dns_byaddr_create().
*
* Requires:
*
* \li 'address' is a valid address.
* \li 'name' is a valid name with a dedicated buffer.
*/
ISC_LANG_ENDDECLS
#endif /* DNS_BYADDR_H */
