/*
* util/storage/dnstree.h - support for rbtree types suitable for DNS code.
*
* Copyright (c) 2008, 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 structures combining types and functions to
* manipulate those structures that help building DNS lookup trees.
*/
#ifndef UTIL_STORAGE_DNSTREE_H
#define UTIL_STORAGE_DNSTREE_H
#include "util/rbtree.h"
/**
* Tree of domain names. Sorted first by class then by name.
* This is not sorted canonically, but fast.
* This can be looked up to obtain a closest encloser parent name.
*
* The tree itself is a rbtree_type.
* This is the element node put as first entry in the client structure.
*/
struct name_tree_node {
/** rbtree node, key is this struct : dclass and name */
rbnode_type node;
/** parent in tree */
struct name_tree_node* parent;
/** name in uncompressed wireformat */
uint8_t* name;
/** length of name */
size_t len;
/** labels in name */
int labs;
/** the class of the name (host order) */
uint16_t dclass;
};
/**
* Tree of IP addresses. Sorted first by protocol, then by bits.
* This can be looked up to obtain the enclosing subnet.
*
* The tree itself is a rbtree_type.
* This is the element node put as first entry in the client structure.
*/
struct addr_tree_node {
/** rbtree node, key is this struct : proto and subnet */
rbnode_type node;
/** parent in tree */
struct addr_tree_node* parent;
/** address */
struct sockaddr_storage addr;
/** length of addr */
socklen_t addrlen;
/** netblock size */
int net;
};
/**
* Init a name tree to be empty
* @param tree: to init.
*/
void name_tree_init(rbtree_type* tree);
/**
* insert element into name tree.
* @param tree: name tree
* @param node: node element (at start of a structure that caller
* has allocated).
* @param name: name to insert (wireformat)
* this node has been allocated by the caller and it itself inserted.
* @param len: length of name
* @param labs: labels in name
* @param dclass: class of name
* @return false on error (duplicate element).
*/
int name_tree_insert(rbtree_type* tree, struct name_tree_node* node,
uint8_t* name, size_t len, int labs, uint16_t dclass);
/**
* Initialize parent pointers in name tree.
* Should be performed after insertions are done, before lookups
* @param tree: name tree
*/
void name_tree_init_parents(rbtree_type* tree);
/**
* Lookup exact match in name tree
* @param tree: name tree
* @param name: wireformat name
* @param len: length of name
* @param labs: labels in name
* @param dclass: class of name
* @return node or NULL if not found.
*/
struct name_tree_node* name_tree_find(rbtree_type* tree, uint8_t* name,
size_t len, int labs, uint16_t dclass);
/**
* Lookup closest encloser in name tree.
* @param tree: name tree
* @param name: wireformat name
* @param len: length of name
* @param labs: labels in name
* @param dclass: class of name
* @return closest enclosing node (could be equal) or NULL if not found.
*/
struct name_tree_node* name_tree_lookup(rbtree_type* tree, uint8_t* name,
size_t len, int labs, uint16_t dclass);
/**
* Find next root item in name tree.
* @param tree: the nametree.
* @param dclass: the class to look for next (or higher).
* @return false if no classes found, true means class put into c.
*/
int name_tree_next_root(rbtree_type* tree, uint16_t* dclass);
/**
* Init addr tree to be empty.
* @param tree: to init.
*/
void addr_tree_init(rbtree_type* tree);
/**
* insert element into addr tree.
* @param tree: addr tree
* @param node: node element (at start of a structure that caller
* has allocated).
* @param addr: to insert (copied).
* @param addrlen: length of addr
* @param net: size of subnet.
* @return false on error (duplicate element).
*/
int addr_tree_insert(rbtree_type* tree, struct addr_tree_node* node,
struct sockaddr_storage* addr, socklen_t addrlen, int net);
/**
* Initialize parent pointers in addr tree.
* Should be performed after insertions are done, before lookups
* @param tree: addr tree
*/
void addr_tree_init_parents(rbtree_type* tree);
/**
* Lookup closest encloser in addr tree.
* @param tree: addr tree
* @param addr: to lookup.
* @param addrlen: length of addr
* @return closest enclosing node (could be equal) or NULL if not found.
*/
struct addr_tree_node* addr_tree_lookup(rbtree_type* tree,
struct sockaddr_storage* addr, socklen_t addrlen);
/**
* Find element in addr tree. (search a netblock, not a match for an address)
* @param tree: addr tree
* @param addr: netblock to lookup.
* @param addrlen: length of addr
* @param net: size of subnet
* @return addr tree element, or NULL if not found.
*/
struct addr_tree_node* addr_tree_find(rbtree_type* tree,
struct sockaddr_storage* addr, socklen_t addrlen, int net);
/** compare name tree nodes */
int name_tree_compare(const void* k1, const void* k2);
/** compare addr tree nodes */
int addr_tree_compare(const void* k1, const void* k2);
#endif /* UTIL_STORAGE_DNSTREE_H */
