monero/external/unbound/iterator/iter_fwd.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

200 lines
6.3 KiB
C

/*
* iterator/iter_fwd.h - iterative resolver module forward zones.
*
* 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 forward zones, and read those from config.
*/
#ifndef ITERATOR_ITER_FWD_H
#define ITERATOR_ITER_FWD_H
#include "util/rbtree.h"
struct config_file;
struct delegpt;
/**
* Iterator forward zones structure
*/
struct iter_forwards {
/**
* Zones 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_forward_zone.
*/
rbtree_type* tree;
};
/**
* Iterator forward servers for a particular zone.
*/
struct iter_forward_zone {
/** redblacktree node, key is this structure: class and name */
rbnode_type node;
/** name */
uint8_t* name;
/** length of name */
size_t namelen;
/** number of labels in name */
int namelabs;
/** delegation point with forward server information for this zone.
* If NULL then this forward entry is used to indicate that a
* stub-zone with the same name exists, and should be used.
* This delegation point is malloced.
*/
struct delegpt* dp;
/** pointer to parent in tree (or NULL if none) */
struct iter_forward_zone* parent;
/** class. host order. */
uint16_t dclass;
};
/**
* Create forwards
* @return new forwards or NULL on error.
*/
struct iter_forwards* forwards_create(void);
/**
* Delete forwards.
* @param fwd: to delete.
*/
void forwards_delete(struct iter_forwards* fwd);
/**
* Process forwards config.
* @param fwd: where to store.
* @param cfg: config options.
* @return 0 on error.
*/
int forwards_apply_cfg(struct iter_forwards* fwd, struct config_file* cfg);
/**
* Find forward zone exactly by name
* @param fwd: forward storage.
* @param qname: The qname of the query.
* @param qclass: The qclass of the query.
* @return: A delegation point or null.
*/
struct delegpt* forwards_find(struct iter_forwards* fwd, uint8_t* qname,
uint16_t qclass);
/**
* Find forward zone information
* For this qname/qclass find forward zone information, returns delegation
* point with server names and addresses, or NULL if no forwarding is needed.
*
* @param fwd: forward storage.
* @param qname: The qname of the query.
* @param qclass: The qclass of the query.
* @return: A delegation point if the query has to be forwarded to that list,
* otherwise null.
*/
struct delegpt* forwards_lookup(struct iter_forwards* fwd,
uint8_t* qname, uint16_t qclass);
/**
* Same as forwards_lookup, but for the root only
* @param fwd: forward storage.
* @param qclass: The qclass of the query.
* @return: A delegation point if root forward exists, otherwise null.
*/
struct delegpt* forwards_lookup_root(struct iter_forwards* fwd,
uint16_t qclass);
/**
* Find next root item in forwards lookup tree.
* @param fwd: the forward storage
* @param qclass: class to look at next, or higher.
* @return false if none found, or if true stored in qclass.
*/
int forwards_next_root(struct iter_forwards* fwd, uint16_t* qclass);
/**
* Get memory in use by forward storage
* @param fwd: forward storage.
* @return bytes in use
*/
size_t forwards_get_mem(struct iter_forwards* fwd);
/** compare two fwd entries */
int fwd_cmp(const void* k1, const void* k2);
/**
* Add zone to forward structure. For external use since it recalcs
* the tree parents.
* @param fwd: the forward data structure
* @param c: class of zone
* @param dp: delegation point with name and target nameservers for new
* forward zone. malloced.
* @return false on failure (out of memory);
*/
int forwards_add_zone(struct iter_forwards* fwd, uint16_t c,
struct delegpt* dp);
/**
* Remove zone from forward structure. For external use since it
* recalcs the tree parents.
* @param fwd: the forward data structure
* @param c: class of zone
* @param nm: name of zone (in uncompressed wireformat).
*/
void forwards_delete_zone(struct iter_forwards* fwd, uint16_t c, uint8_t* nm);
/**
* Add stub hole (empty entry in forward table, that makes resolution skip
* a forward-zone because the stub zone should override the forward zone).
* Does not add one if not necessary.
* @param fwd: the forward data structure
* @param c: class of zone
* @param nm: name of zone (in uncompressed wireformat).
* @return false on failure (out of memory);
*/
int forwards_add_stub_hole(struct iter_forwards* fwd, uint16_t c, uint8_t* nm);
/**
* Remove stub hole, if one exists.
* @param fwd: the forward data structure
* @param c: class of zone
* @param nm: name of zone (in uncompressed wireformat).
*/
void forwards_delete_stub_hole(struct iter_forwards* fwd, uint16_t c,
uint8_t* nm);
#endif /* ITERATOR_ITER_FWD_H */