← Back
Editing: radix.h
/* * 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 */
Save File
Cancel