diff options
Diffstat (limited to 'lib/dns/order.c')
| -rw-r--r-- | lib/dns/order.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/lib/dns/order.c b/lib/dns/order.c new file mode 100644 index 0000000..477576c --- /dev/null +++ b/lib/dns/order.c @@ -0,0 +1,150 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * SPDX-License-Identifier: MPL-2.0 + * + * 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. + */ + +/*! \file */ + +#include <stdbool.h> + +#include <isc/magic.h> +#include <isc/mem.h> +#include <isc/refcount.h> +#include <isc/types.h> +#include <isc/util.h> + +#include <dns/fixedname.h> +#include <dns/name.h> +#include <dns/order.h> +#include <dns/rdataset.h> +#include <dns/types.h> + +typedef struct dns_order_ent dns_order_ent_t; +struct dns_order_ent { + dns_fixedname_t name; + dns_rdataclass_t rdclass; + dns_rdatatype_t rdtype; + unsigned int mode; + ISC_LINK(dns_order_ent_t) link; +}; + +struct dns_order { + unsigned int magic; + isc_refcount_t references; + ISC_LIST(dns_order_ent_t) ents; + isc_mem_t *mctx; +}; + +#define DNS_ORDER_MAGIC ISC_MAGIC('O', 'r', 'd', 'r') +#define DNS_ORDER_VALID(order) ISC_MAGIC_VALID(order, DNS_ORDER_MAGIC) + +isc_result_t +dns_order_create(isc_mem_t *mctx, dns_order_t **orderp) { + dns_order_t *order; + + REQUIRE(orderp != NULL && *orderp == NULL); + + order = isc_mem_get(mctx, sizeof(*order)); + + ISC_LIST_INIT(order->ents); + + /* Implicit attach. */ + isc_refcount_init(&order->references, 1); + + order->mctx = NULL; + isc_mem_attach(mctx, &order->mctx); + order->magic = DNS_ORDER_MAGIC; + *orderp = order; + return (ISC_R_SUCCESS); +} + +isc_result_t +dns_order_add(dns_order_t *order, const dns_name_t *name, + dns_rdatatype_t rdtype, dns_rdataclass_t rdclass, + unsigned int mode) { + dns_order_ent_t *ent; + + REQUIRE(DNS_ORDER_VALID(order)); + REQUIRE(mode == DNS_RDATASETATTR_RANDOMIZE || + mode == DNS_RDATASETATTR_FIXEDORDER || + mode == DNS_RDATASETATTR_CYCLIC || + mode == DNS_RDATASETATTR_NONE); + + ent = isc_mem_get(order->mctx, sizeof(*ent)); + + dns_fixedname_init(&ent->name); + dns_name_copy(name, dns_fixedname_name(&ent->name)); + ent->rdtype = rdtype; + ent->rdclass = rdclass; + ent->mode = mode; + ISC_LINK_INIT(ent, link); + ISC_LIST_INITANDAPPEND(order->ents, ent, link); + return (ISC_R_SUCCESS); +} + +static bool +match(const dns_name_t *name1, const dns_name_t *name2) { + if (dns_name_iswildcard(name2)) { + return (dns_name_matcheswildcard(name1, name2)); + } + return (dns_name_equal(name1, name2)); +} + +unsigned int +dns_order_find(dns_order_t *order, const dns_name_t *name, + dns_rdatatype_t rdtype, dns_rdataclass_t rdclass) { + dns_order_ent_t *ent; + REQUIRE(DNS_ORDER_VALID(order)); + + for (ent = ISC_LIST_HEAD(order->ents); ent != NULL; + ent = ISC_LIST_NEXT(ent, link)) + { + if (ent->rdtype != rdtype && ent->rdtype != dns_rdatatype_any) { + continue; + } + if (ent->rdclass != rdclass && + ent->rdclass != dns_rdataclass_any) + { + continue; + } + if (match(name, dns_fixedname_name(&ent->name))) { + return (ent->mode); + } + } + return (DNS_RDATASETATTR_NONE); +} + +void +dns_order_attach(dns_order_t *source, dns_order_t **target) { + REQUIRE(DNS_ORDER_VALID(source)); + REQUIRE(target != NULL && *target == NULL); + isc_refcount_increment(&source->references); + *target = source; +} + +void +dns_order_detach(dns_order_t **orderp) { + REQUIRE(orderp != NULL && DNS_ORDER_VALID(*orderp)); + dns_order_t *order; + order = *orderp; + *orderp = NULL; + + if (isc_refcount_decrement(&order->references) == 1) { + isc_refcount_destroy(&order->references); + order->magic = 0; + dns_order_ent_t *ent; + while ((ent = ISC_LIST_HEAD(order->ents)) != NULL) { + ISC_LIST_UNLINK(order->ents, ent, link); + isc_mem_put(order->mctx, ent, sizeof(*ent)); + } + isc_mem_putanddetach(&order->mctx, order, sizeof(*order)); + } +} |