danicoin/external/unbound/iterator/iter_hints.h
Erik de Castro Lopo a85b5759f3 Upgrade unbound library
These files were pulled from the 1.6.3 release tarball.

This new version builds against OpenSSL version 1.1 which will be
the default in the new Debian Stable which is due to be released
RealSoonNow (tm).
2017-06-17 23:04:00 +10:00

161 lines
5.4 KiB
C

/*
* iterator/iter_hints.h - iterative resolver module stub and root hints.
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the NLNET LABS nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* \file
*
* This file contains functions to assist the iterator module.
* Keep track of stub and root hints, and read those from config.
*/
#ifndef ITERATOR_ITER_HINTS_H
#define ITERATOR_ITER_HINTS_H
#include "util/storage/dnstree.h"
struct iter_env;
struct config_file;
struct delegpt;
/**
* Iterator hints structure
*/
struct iter_hints {
/**
* Hints are stored in this tree. Sort order is specially chosen.
* first sorted on qclass. Then on dname in nsec-like order, so that
* a lookup on class, name will return an exact match or the closest
* match which gives the ancestor needed.
* contents of type iter_hints_stub. The class IN root is in here.
* uses name_tree_node from dnstree.h.
*/
rbtree_type tree;
};
/**
* Iterator hints for a particular stub.
*/
struct iter_hints_stub {
/** tree sorted by name, class */
struct name_tree_node node;
/** delegation point with hint information for this stub. malloced. */
struct delegpt* dp;
/** does the stub need to forego priming (like on other ports) */
uint8_t noprime;
};
/**
* Create hints
* @return new hints or NULL on error.
*/
struct iter_hints* hints_create(void);
/**
* Delete hints.
* @param hints: to delete.
*/
void hints_delete(struct iter_hints* hints);
/**
* Process hints config. Sets default values for root hints if no config.
* @param hints: where to store.
* @param cfg: config options.
* @return 0 on error.
*/
int hints_apply_cfg(struct iter_hints* hints, struct config_file* cfg);
/**
* Find root hints for the given class.
* @param hints: hint storage.
* @param qclass: class for which root hints are requested. host order.
* @return: NULL if no hints, or a ptr to stored hints.
*/
struct delegpt* hints_lookup_root(struct iter_hints* hints, uint16_t qclass);
/**
* Find next root hints (to cycle through all root hints).
* @param hints: hint storage
* @param qclass: class for which root hints are sought.
* 0 means give the first available root hints class.
* x means, give class x or a higher class if any.
* returns the found class in this variable.
* @return true if a root hint class is found.
* false if not root hint class is found (qclass may have been changed).
*/
int hints_next_root(struct iter_hints* hints, uint16_t* qclass);
/**
* Given a qname/qclass combination, and the delegation point from the cache
* for this qname/qclass, determine if this combination indicates that a
* stub hint exists and must be primed.
*
* @param hints: hint storage.
* @param qname: The qname that generated the delegation point.
* @param qclass: The qclass that generated the delegation point.
* @param dp: The cache generated delegation point.
* @return: A priming delegation point if there is a stub hint that must
* be primed, otherwise null.
*/
struct iter_hints_stub* hints_lookup_stub(struct iter_hints* hints,
uint8_t* qname, uint16_t qclass, struct delegpt* dp);
/**
* Get memory in use by hints
* @param hints: hint storage.
* @return bytes in use
*/
size_t hints_get_mem(struct iter_hints* hints);
/**
* Add stub to hints structure. For external use since it recalcs
* the tree parents.
* @param hints: the hints data structure
* @param c: class of zone
* @param dp: delegation point with name and target nameservers for new
* hints stub. malloced.
* @param noprime: set noprime option to true or false on new hint stub.
* @return false on failure (out of memory);
*/
int hints_add_stub(struct iter_hints* hints, uint16_t c, struct delegpt* dp,
int noprime);
/**
* Remove stub from hints structure. For external use since it
* recalcs the tree parents.
* @param hints: the hints data structure
* @param c: class of stub zone
* @param nm: name of stub zone (in uncompressed wireformat).
*/
void hints_delete_stub(struct iter_hints* hints, uint16_t c, uint8_t* nm);
#endif /* ITERATOR_ITER_HINTS_H */