forward.c revision 0c27b3fe77ac1d5094ba3521e8142d9e7973133f
/*
* Copyright (C) 2000, 2001, 2004, 2005, 2007, 2009, 2013, 2016 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 http://mozilla.org/MPL/2.0/.
*/
/*! \file */
#include <config.h>
#include <isc/magic.h>
#include <isc/mem.h>
#include <isc/rwlock.h>
#include <isc/util.h>
#include <dns/forward.h>
#include <dns/rbt.h>
#include <dns/result.h>
#include <dns/types.h>
struct dns_fwdtable {
/* Unlocked. */
unsigned int magic;
isc_mem_t *mctx;
isc_rwlock_t rwlock;
/* Locked by lock. */
dns_rbt_t *table;
};
#define FWDTABLEMAGIC ISC_MAGIC('F', 'w', 'd', 'T')
#define VALID_FWDTABLE(ft) ISC_MAGIC_VALID(ft, FWDTABLEMAGIC)
static void
auto_detach(void *, void *);
isc_result_t
dns_fwdtable_create(isc_mem_t *mctx, dns_fwdtable_t **fwdtablep) {
dns_fwdtable_t *fwdtable;
isc_result_t result;
REQUIRE(fwdtablep != NULL && *fwdtablep == NULL);
fwdtable = isc_mem_get(mctx, sizeof(dns_fwdtable_t));
if (fwdtable == NULL)
return (ISC_R_NOMEMORY);
fwdtable->table = NULL;
result = dns_rbt_create(mctx, auto_detach, fwdtable, &fwdtable->table);
if (result != ISC_R_SUCCESS)
goto cleanup_fwdtable;
result = isc_rwlock_init(&fwdtable->rwlock, 0, 0);
if (result != ISC_R_SUCCESS)
goto cleanup_rbt;
fwdtable->mctx = NULL;
isc_mem_attach(mctx, &fwdtable->mctx);
fwdtable->magic = FWDTABLEMAGIC;
*fwdtablep = fwdtable;
return (ISC_R_SUCCESS);
cleanup_rbt:
dns_rbt_destroy(&fwdtable->table);
cleanup_fwdtable:
isc_mem_put(mctx, fwdtable, sizeof(dns_fwdtable_t));
return (result);
}
isc_result_t
dns_fwdtable_addfwd(dns_fwdtable_t *fwdtable, dns_name_t *name,
dns_forwarderlist_t *fwdrs, dns_fwdpolicy_t fwdpolicy)
{
isc_result_t result;
dns_forwarders_t *forwarders;
dns_forwarder_t *fwd, *nfwd;
REQUIRE(VALID_FWDTABLE(fwdtable));
forwarders = isc_mem_get(fwdtable->mctx, sizeof(dns_forwarders_t));
if (forwarders == NULL)
return (ISC_R_NOMEMORY);
ISC_LIST_INIT(forwarders->fwdrs);
for (fwd = ISC_LIST_HEAD(*fwdrs);
fwd != NULL;
fwd = ISC_LIST_NEXT(fwd, link))
{
nfwd = isc_mem_get(fwdtable->mctx, sizeof(dns_forwarder_t));
if (nfwd == NULL) {
result = ISC_R_NOMEMORY;
goto cleanup;
}
*nfwd = *fwd;
ISC_LINK_INIT(nfwd, link);
ISC_LIST_APPEND(forwarders->fwdrs, nfwd, link);
}
forwarders->fwdpolicy = fwdpolicy;
RWLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
result = dns_rbt_addname(fwdtable->table, name, forwarders);
RWUNLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
if (result != ISC_R_SUCCESS)
goto cleanup;
return (ISC_R_SUCCESS);
cleanup:
while (!ISC_LIST_EMPTY(forwarders->fwdrs)) {
fwd = ISC_LIST_HEAD(forwarders->fwdrs);
ISC_LIST_UNLINK(forwarders->fwdrs, fwd, link);
isc_mem_put(fwdtable->mctx, fwd, sizeof(isc_sockaddr_t));
}
isc_mem_put(fwdtable->mctx, forwarders, sizeof(dns_forwarders_t));
return (result);
}
isc_result_t
dns_fwdtable_add(dns_fwdtable_t *fwdtable, dns_name_t *name,
isc_sockaddrlist_t *addrs, dns_fwdpolicy_t fwdpolicy)
{
isc_result_t result;
dns_forwarders_t *forwarders;
dns_forwarder_t *fwd;
isc_sockaddr_t *sa;
REQUIRE(VALID_FWDTABLE(fwdtable));
forwarders = isc_mem_get(fwdtable->mctx, sizeof(dns_forwarders_t));
if (forwarders == NULL)
return (ISC_R_NOMEMORY);
ISC_LIST_INIT(forwarders->fwdrs);
for (sa = ISC_LIST_HEAD(*addrs);
sa != NULL;
sa = ISC_LIST_NEXT(sa, link))
{
fwd = isc_mem_get(fwdtable->mctx, sizeof(dns_forwarder_t));
if (fwd == NULL) {
result = ISC_R_NOMEMORY;
goto cleanup;
}
fwd->addr = *sa;
fwd->dscp = -1;
ISC_LINK_INIT(fwd, link);
ISC_LIST_APPEND(forwarders->fwdrs, fwd, link);
}
forwarders->fwdpolicy = fwdpolicy;
RWLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
result = dns_rbt_addname(fwdtable->table, name, forwarders);
RWUNLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
if (result != ISC_R_SUCCESS)
goto cleanup;
return (ISC_R_SUCCESS);
cleanup:
while (!ISC_LIST_EMPTY(forwarders->fwdrs)) {
fwd = ISC_LIST_HEAD(forwarders->fwdrs);
ISC_LIST_UNLINK(forwarders->fwdrs, fwd, link);
isc_mem_put(fwdtable->mctx, fwd, sizeof(dns_forwarder_t));
}
isc_mem_put(fwdtable->mctx, forwarders, sizeof(dns_forwarders_t));
return (result);
}
isc_result_t
dns_fwdtable_delete(dns_fwdtable_t *fwdtable, dns_name_t *name) {
isc_result_t result;
REQUIRE(VALID_FWDTABLE(fwdtable));
RWLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
result = dns_rbt_deletename(fwdtable->table, name, ISC_FALSE);
RWUNLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
if (result == DNS_R_PARTIALMATCH)
result = ISC_R_NOTFOUND;
return (result);
}
isc_result_t
dns_fwdtable_find(dns_fwdtable_t *fwdtable, dns_name_t *name,
dns_forwarders_t **forwardersp)
{
return (dns_fwdtable_find2(fwdtable, name, NULL, forwardersp));
}
isc_result_t
dns_fwdtable_find2(dns_fwdtable_t *fwdtable, dns_name_t *name,
dns_name_t *foundname, dns_forwarders_t **forwardersp)
{
isc_result_t result;
REQUIRE(VALID_FWDTABLE(fwdtable));
RWLOCK(&fwdtable->rwlock, isc_rwlocktype_read);
result = dns_rbt_findname(fwdtable->table, name, 0, foundname,
(void **)forwardersp);
if (result == DNS_R_PARTIALMATCH)
result = ISC_R_SUCCESS;
RWUNLOCK(&fwdtable->rwlock, isc_rwlocktype_read);
return (result);
}
void
dns_fwdtable_destroy(dns_fwdtable_t **fwdtablep) {
dns_fwdtable_t *fwdtable;
isc_mem_t *mctx;
REQUIRE(fwdtablep != NULL && VALID_FWDTABLE(*fwdtablep));
fwdtable = *fwdtablep;
dns_rbt_destroy(&fwdtable->table);
isc_rwlock_destroy(&fwdtable->rwlock);
fwdtable->magic = 0;
mctx = fwdtable->mctx;
isc_mem_put(mctx, fwdtable, sizeof(dns_fwdtable_t));
isc_mem_detach(&mctx);
*fwdtablep = NULL;
}
/***
*** Private
***/
static void
auto_detach(void *data, void *arg) {
dns_forwarders_t *forwarders = data;
dns_fwdtable_t *fwdtable = arg;
dns_forwarder_t *fwd;
UNUSED(arg);
while (!ISC_LIST_EMPTY(forwarders->fwdrs)) {
fwd = ISC_LIST_HEAD(forwarders->fwdrs);
ISC_LIST_UNLINK(forwarders->fwdrs, fwd, link);
isc_mem_put(fwdtable->mctx, fwd, sizeof(dns_forwarder_t));
}
isc_mem_put(fwdtable->mctx, forwarders, sizeof(dns_forwarders_t));
}