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/*
* 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.
*/
#include <stdbool.h>
#include <isc/magic.h>
#include <isc/types.h>
#include <isc/mutex.h>
#include <isc/net.h>
#include <isc/refcount.h>
#include <string.h>
#ifndef _RADIX_H
#define _RADIX_H
#define NETADDR_TO_PREFIX_T(na,pt,bits,is_ecs) \
do { \
const void *p = na; \
memset(&(pt), 0, sizeof(pt)); \
if (p != NULL) { \
(pt).family = (na)->family; \
(pt).bitlen = (bits); \
if ((pt).family == AF_INET6) { \
memmove(&(pt).add.sin6, &(na)->type.in6, \
((bits)+7)/8); \
} else \
memmove(&(pt).add.sin, &(na)->type.in, \
((bits)+7)/8); \
} else { \
(pt).family = AF_UNSPEC; \
(pt).bitlen = 0; \
} \
(pt).ecs = is_ecs; \
isc_refcount_init(&(pt).refcount, 0); \
} while(0)
typedef struct isc_prefix {
isc_mem_t *mctx;
unsigned int family; /* AF_INET | AF_INET6, or AF_UNSPEC for "any" */
unsigned int bitlen; /* 0 for "any" */
bool ecs; /* true for an EDNS client subnet address */
isc_refcount_t refcount;
union {
struct in_addr sin;
struct in6_addr sin6;
} add;
} isc_prefix_t;
typedef void (*isc_radix_destroyfunc_t)(void *);
typedef void (*isc_radix_processfunc_t)(isc_prefix_t *, void **);
#define isc_prefix_tochar(prefix) ((char *)&(prefix)->add.sin)
#define isc_prefix_touchar(prefix) ((u_char *)&(prefix)->add.sin)
/*
* We need "first match" when we search the radix tree to preserve
* compatibility with the existing ACL implementation. Radix trees
* naturally lend themselves to "best match". In order to get "first match"
* behavior, we keep track of the order in which entries are added to the
* tree--and when a search is made, we find all matching entries, and
* return the one that was added first.
*
* An IPv4 prefix and an IPv6 prefix may share a radix tree node if they
* have the same length and bit pattern (e.g., 127/8 and 7f::/8). Also,
* a node that matches a client address may also match an EDNS client
* subnet address. To disambiguate between these, node_num and data
* are four-element arrays;
*
* - node_num[0] and data[0] are used for IPv4 client addresses
* - node_num[1] and data[1] for IPv4 client subnet addresses
* - node_num[2] and data[2] are used for IPv6 client addresses
* - node_num[3] and data[3] for IPv6 client subnet addresses
*
* A prefix of 0/0 (aka "any" or "none"), is always stored as IPv4,
* but matches IPv6 addresses too, as well as all client subnet
* addresses.
*/
#define RADIX_NOECS 0
#define RADIX_ECS 2
#define RADIX_V4 0
#define RADIX_V6 1
#define RADIX_V4_ECS 2
#define RADIX_V6_ECS 3
#define RADIX_FAMILIES 4
#define ISC_RADIX_FAMILY(p) \
((((p)->family == AF_INET6) ? RADIX_V6 : RADIX_V4) + \
((p)->ecs ? RADIX_ECS : RADIX_NOECS))
typedef struct isc_radix_node {
isc_mem_t *mctx;
uint32_t bit; /* bit length of the prefix */
isc_prefix_t *prefix; /* who we are in radix tree */
struct isc_radix_node *l, *r; /* left and right children */
struct isc_radix_node *parent; /* may be used */
void *data[RADIX_FAMILIES]; /* pointers to IPv4 and IPV6 data */
int node_num[RADIX_FAMILIES]; /* which node this was in the tree,
or -1 for glue nodes */
} isc_radix_node_t;
#define RADIX_TREE_MAGIC ISC_MAGIC('R','d','x','T');
#define RADIX_TREE_VALID(a) ISC_MAGIC_VALID(a, RADIX_TREE_MAGIC);
typedef struct isc_radix_tree {
unsigned int magic;
isc_mem_t *mctx;
isc_radix_node_t *head;
uint32_t maxbits; /* for IP, 32 bit addresses */
int num_active_node; /* for debugging purposes */
int num_added_node; /* total number of nodes */
} isc_radix_tree_t;
isc_result_t
isc_radix_search(isc_radix_tree_t *radix, isc_radix_node_t **target,
isc_prefix_t *prefix);
/*%<
* Search 'radix' for the best match to 'prefix'.
* Return the node found in '*target'.
*
* Requires:
* \li 'radix' to be valid.
* \li 'target' is not NULL and "*target" is NULL.
* \li 'prefix' to be valid.
*
* Returns:
* \li ISC_R_NOTFOUND
* \li ISC_R_SUCCESS
*/
isc_result_t
isc_radix_insert(isc_radix_tree_t *radix, isc_radix_node_t **target,
isc_radix_node_t *source, isc_prefix_t *prefix);
/*%<
* Insert 'source' or 'prefix' into the radix tree 'radix'.
* Return the node added in 'target'.
*
* Requires:
* \li 'radix' to be valid.
* \li 'target' is not NULL and "*target" is NULL.
* \li 'prefix' to be valid or 'source' to be non NULL and contain
* a valid prefix.
*
* Returns:
* \li ISC_R_NOMEMORY
* \li ISC_R_SUCCESS
*/
void
isc_radix_remove(isc_radix_tree_t *radix, isc_radix_node_t *node);
/*%<
* Remove the node 'node' from the radix tree 'radix'.
*
* Requires:
* \li 'radix' to be valid.
* \li 'node' to be valid.
*/
isc_result_t
isc_radix_create(isc_mem_t *mctx, isc_radix_tree_t **target, int maxbits);
/*%<
* Create a radix tree with a maximum depth of 'maxbits';
*
* Requires:
* \li 'mctx' to be valid.
* \li 'target' to be non NULL and '*target' to be NULL.
* \li 'maxbits' to be less than or equal to RADIX_MAXBITS.
*
* Returns:
* \li ISC_R_NOMEMORY
* \li ISC_R_SUCCESS
*/
void
isc_radix_destroy(isc_radix_tree_t *radix, isc_radix_destroyfunc_t func);
/*%<
* Destroy a radix tree optionally calling 'func' to clean up node data.
*
* Requires:
* \li 'radix' to be valid.
*/
void
isc_radix_process(isc_radix_tree_t *radix, isc_radix_processfunc_t func);
/*%<
* Walk a radix tree calling 'func' to process node data.
*
* Requires:
* \li 'radix' to be valid.
* \li 'func' to point to a function.
*/
#define RADIX_MAXBITS 128
#define RADIX_NBIT(x) (0x80 >> ((x) & 0x7f))
#define RADIX_NBYTE(x) ((x) >> 3)
#define RADIX_WALK(Xhead, Xnode) \
do { \
isc_radix_node_t *Xstack[RADIX_MAXBITS+1]; \
isc_radix_node_t **Xsp = Xstack; \
isc_radix_node_t *Xrn = (Xhead); \
while ((Xnode = Xrn)) { \
if (Xnode->prefix)
#define RADIX_WALK_END \
if (Xrn->l) { \
if (Xrn->r) { \
*Xsp++ = Xrn->r; \
} \
Xrn = Xrn->l; \
} else if (Xrn->r) { \
Xrn = Xrn->r; \
} else if (Xsp != Xstack) { \
Xrn = *(--Xsp); \
} else { \
Xrn = (isc_radix_node_t *) 0; \
} \
} \
} while (0)
#endif /* _RADIX_H */
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