/contrib/bind9/lib/dns/order.c

  1/*
  2 * Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
  3 * Copyright (C) 2002  Internet Software Consortium.
  4 *
  5 * Permission to use, copy, modify, and/or distribute this software for any
  6 * purpose with or without fee is hereby granted, provided that the above
  7 * copyright notice and this permission notice appear in all copies.
  8 *
  9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 11 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 15 * PERFORMANCE OF THIS SOFTWARE.
 16 */
 17
 18/* $Id: order.c,v 1.10 2007/06/19 23:47:16 tbox Exp $ */
 19
 20/*! \file */
 21
 22#include <config.h>
 23
 24#include <isc/magic.h>
 25#include <isc/mem.h>
 26#include <isc/types.h>
 27#include <isc/util.h>
 28#include <isc/refcount.h>
 29
 30#include <dns/fixedname.h>
 31#include <dns/name.h>
 32#include <dns/order.h>
 33#include <dns/rdataset.h>
 34#include <dns/types.h>
 35
 36typedef struct dns_order_ent dns_order_ent_t;
 37struct dns_order_ent {
 38	dns_fixedname_t			name;
 39	dns_rdataclass_t		rdclass;
 40	dns_rdatatype_t			rdtype;
 41	unsigned int			mode;
 42	ISC_LINK(dns_order_ent_t)	link;
 43};
 44
 45struct dns_order {
 46	unsigned int			magic;
 47	isc_refcount_t          	references;
 48	ISC_LIST(dns_order_ent_t)	ents;
 49	isc_mem_t			*mctx;
 50};
 51	
 52#define DNS_ORDER_MAGIC ISC_MAGIC('O','r','d','r')
 53#define DNS_ORDER_VALID(order)	ISC_MAGIC_VALID(order, DNS_ORDER_MAGIC)
 54
 55isc_result_t
 56dns_order_create(isc_mem_t *mctx, dns_order_t **orderp) {
 57	dns_order_t *order;
 58	isc_result_t result;
 59
 60	REQUIRE(orderp != NULL && *orderp == NULL);
 61
 62	order = isc_mem_get(mctx, sizeof(*order));
 63	if (order == NULL)
 64		return (ISC_R_NOMEMORY);
 65	
 66	ISC_LIST_INIT(order->ents);
 67
 68	/* Implicit attach. */
 69	result = isc_refcount_init(&order->references, 1);
 70	if (result != ISC_R_SUCCESS) {
 71		isc_mem_put(mctx, order, sizeof(*order));
 72		return (result);
 73	}
 74
 75	order->mctx = NULL;
 76	isc_mem_attach(mctx, &order->mctx);
 77	order->magic = DNS_ORDER_MAGIC;
 78	*orderp = order;
 79	return (ISC_R_SUCCESS);
 80}
 81
 82isc_result_t
 83dns_order_add(dns_order_t *order, dns_name_t *name,
 84	      dns_rdatatype_t rdtype, dns_rdataclass_t rdclass,
 85	      unsigned int mode)
 86{
 87	dns_order_ent_t *ent;
 88
 89	REQUIRE(DNS_ORDER_VALID(order));
 90	REQUIRE(mode == DNS_RDATASETATTR_RANDOMIZE ||
 91	        mode == DNS_RDATASETATTR_FIXEDORDER ||
 92		mode == 0 /* DNS_RDATASETATTR_CYCLIC */ );
 93
 94	ent = isc_mem_get(order->mctx, sizeof(*ent));
 95	if (ent == NULL)
 96		return (ISC_R_NOMEMORY);
 97
 98	dns_fixedname_init(&ent->name);
 99	RUNTIME_CHECK(dns_name_copy(name, dns_fixedname_name(&ent->name), NULL)
100		      == ISC_R_SUCCESS);
101	ent->rdtype = rdtype;
102	ent->rdclass = rdclass;
103	ent->mode = mode;
104	ISC_LINK_INIT(ent, link);
105	ISC_LIST_INITANDAPPEND(order->ents, ent, link);
106	return (ISC_R_SUCCESS);
107}
108
109static inline isc_boolean_t
110match(dns_name_t *name1, dns_name_t *name2) {
111	
112	if (dns_name_iswildcard(name2))
113		return(dns_name_matcheswildcard(name1, name2));
114	return (dns_name_equal(name1, name2));
115}
116
117unsigned int
118dns_order_find(dns_order_t *order, dns_name_t *name,
119	       dns_rdatatype_t rdtype, dns_rdataclass_t rdclass)
120{
121	dns_order_ent_t *ent;
122	REQUIRE(DNS_ORDER_VALID(order));
123
124	for (ent = ISC_LIST_HEAD(order->ents);
125	     ent != NULL;
126	     ent = ISC_LIST_NEXT(ent, link)) {
127		if (ent->rdtype != rdtype && ent->rdtype != dns_rdatatype_any)
128			continue;
129		if (ent->rdclass != rdclass &&
130		    ent->rdclass != dns_rdataclass_any)
131			continue;
132		if (match(name, dns_fixedname_name(&ent->name)))
133			return (ent->mode);
134	}
135	return (0);
136}
137
138void
139dns_order_attach(dns_order_t *source, dns_order_t **target) {
140	REQUIRE(DNS_ORDER_VALID(source));
141	REQUIRE(target != NULL && *target == NULL);
142	isc_refcount_increment(&source->references, NULL);
143	*target = source;
144}
145
146void
147dns_order_detach(dns_order_t **orderp) {
148	dns_order_t *order;
149	dns_order_ent_t *ent;
150	unsigned int references;
151
152	REQUIRE(orderp != NULL);
153	order = *orderp;
154	REQUIRE(DNS_ORDER_VALID(order));
155	isc_refcount_decrement(&order->references, &references);
156	*orderp = NULL;
157	if (references != 0)
158		return;
159
160	order->magic = 0;
161	while ((ent = ISC_LIST_HEAD(order->ents)) != NULL) {
162		ISC_LIST_UNLINK(order->ents, ent, link);
163		isc_mem_put(order->mctx, ent, sizeof(*ent));
164	}
165	isc_refcount_destroy(&order->references);
166	isc_mem_putanddetach(&order->mctx, order, sizeof(*order));
167}