/* * Copyright (C) 2002 Stichting NLnet, Netherlands, stichting@nlnet.nl. * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the * above copyright notice and this permission notice appear in all * copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND STICHTING NLNET * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL * STICHTING NLNET BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE * USE OR PERFORMANCE OF THIS SOFTWARE. * * The development of Dynamically Loadable Zones (DLZ) for Bind 9 was * conceived and contributed by Rob Butler. * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the * above copyright notice and this permission notice appear in all * copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND ROB BUTLER * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL * ROB BUTLER BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE * USE OR PERFORMANCE OF THIS SOFTWARE. */ /* * Copyright (C) 1999-2001, 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/. */ #ifdef DLZ_BDB #include #include #include #include #include #include #include #include #include #include #include #include #include #include static dns_sdlzimplementation_t *dlz_bdbhpt = NULL; /* should the bdb driver use threads. */ #ifdef ISC_PLATFORM_USETHREADS #define bdbhpt_threads DB_THREAD #else #define bdbhpt_threads 0 #endif /* bdbhpt database names */ #define dlz_data "dns_data" #define dlz_zone "dns_zone" #define dlz_xfr "dns_xfr" #define dlz_client "dns_client" /* This structure contains all the Berkeley DB handles * for this instance of the bdbhpt driver. */ typedef struct bdbhpt_instance { DB_ENV *dbenv; /*%< bdbhpt environment */ DB *data; /*%< dns_data database handle */ DB *zone; /*%< zone database handle */ DB *xfr; /*%< zone xfr database handle */ DB *client; /*%< client database handle */ isc_mem_t *mctx; /*%< memory context */ } bdbhpt_instance_t; typedef struct bdbhpt_parsed_data { char *host; char *type; int ttl; char *data; } bdbhpt_parsed_data_t; /* forward reference */ static isc_result_t bdbhpt_findzone(void *driverarg, void *dbdata, const char *name, dns_clientinfomethods_t *methods, dns_clientinfo_t *clientinfo); /*% * Reverses a string in place. */ static char *bdbhpt_strrev(char *str) { char *p1, *p2; if (! str || ! *str) return str; for (p1 = str, p2 = str + strlen(str) - 1; p2 > p1; ++p1, --p2) { *p1 ^= *p2; *p2 ^= *p1; *p1 ^= *p2; } return str; } /*% * Parses the DBT from the Berkeley DB into a parsed_data record * The parsed_data record should be allocated before and passed into the * bdbhpt_parse_data function. The char (type & data) fields should not * be "free"d as that memory is part of the DBT data field. It will be * "free"d when the DBT is freed. */ static isc_result_t bdbhpt_parse_data(char *in, bdbhpt_parsed_data_t *pd) { char *endp, *ttlStr; char *tmp = in; char *lastchar = (char *) &tmp[strlen(tmp)]; /*% * String should be formated as: * replication_id * (a space) * host_name * (a space) * ttl * (a space) * type * (a space) * remaining data * * examples: * * 9191 host 10 A 127.0.0.1 * server1_212 host 10 A 127.0.0.2 * {xxxx-xxxx-xxxx-xxxx-xxxx} host 10 MX 20 mail.example.com */ /* * we don't need the replication id, so don't * bother saving a pointer to it. */ /* find space after replication id */ tmp = strchr(tmp, ' '); /* verify we found a space */ if (tmp == NULL) return ISC_R_FAILURE; /* make sure it is safe to increment pointer */ if (++tmp > lastchar) return ISC_R_FAILURE; /* save pointer to host */ pd->host = tmp; /* find space after host and change it to a '\0' */ tmp = strchr(tmp, ' '); /* verify we found a space */ if (tmp == NULL) return ISC_R_FAILURE; /* change the space to a null (string terminator) */ tmp[0] = '\0'; /* make sure it is safe to increment pointer */ if (++tmp > lastchar) return ISC_R_FAILURE; /* save pointer to ttl string */ ttlStr = tmp; /* find space after ttl and change it to a '\0' */ tmp = strchr(tmp, ' '); /* verify we found a space */ if (tmp == NULL) return ISC_R_FAILURE; /* change the space to a null (string terminator) */ tmp[0] = '\0'; /* make sure it is safe to increment pointer */ if (++tmp > lastchar) return ISC_R_FAILURE; /* save pointer to dns type */ pd->type = tmp; /* find space after type and change it to a '\0' */ tmp = strchr(tmp, ' '); /* verify we found a space */ if (tmp == NULL) return ISC_R_FAILURE; /* change the space to a null (string terminator) */ tmp[0] = '\0'; /* make sure it is safe to increment pointer */ if (++tmp > lastchar) return ISC_R_FAILURE; /* save pointer to remainder of DNS data */ pd->data = tmp; /* convert ttl string to integer */ pd->ttl = strtol(ttlStr, &endp, 10); if (*endp != '\0' || pd->ttl < 0) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, "bdbhpt driver ttl must be a postive number"); return ISC_R_FAILURE; } /* if we get this far everything should have worked. */ return ISC_R_SUCCESS; } /* * DLZ methods */ static isc_result_t bdbhpt_allowzonexfr(void *driverarg, void *dbdata, const char *name, const char *client) { isc_result_t result; bdbhpt_instance_t *db = (bdbhpt_instance_t *) dbdata; DBT key, data; /* check to see if we are authoritative for the zone first. */ result = bdbhpt_findzone(driverarg, dbdata, name, NULL, NULL); if (result != ISC_R_SUCCESS) return (ISC_R_NOTFOUND); memset(&key, 0, sizeof(DBT)); key.flags = DB_DBT_MALLOC; key.data = strdup(name); if (key.data == NULL) { result = ISC_R_NOMEMORY; goto xfr_cleanup; } key.size = strlen(key.data); memset(&data, 0, sizeof(DBT)); data.flags = DB_DBT_MALLOC; data.data = strdup(client); if (data.data == NULL) { result = ISC_R_NOMEMORY; goto xfr_cleanup; } data.size = strlen(data.data); switch(db->client->get(db->client, NULL, &key, &data, DB_GET_BOTH)) { case DB_NOTFOUND: result = ISC_R_NOTFOUND; break; case 0: result = ISC_R_SUCCESS; break; default: result = ISC_R_FAILURE; } xfr_cleanup: /* free any memory duplicate string in the key field */ if (key.data != NULL) free(key.data); /* free any memory allocated to the data field. */ if (data.data != NULL) free(data.data); return result; } /*% * BDB does not allow a secondary index on a database that allows * duplicates. We have a few options: * * 1) kill speed by having lookup method use a secondary db which * is associated to the primary DB with the DNS data. Then have * another secondary db for zone transfer which also points to * the dns_data primary. NO - The point of this driver is * lookup performance. * * 2) Blow up database size by storing DNS data twice. Once for * the lookup (dns_data) database, and a second time for the zone * transfer (dns_xfr) database. NO - That would probably require * a larger cache to provide good performance. Also, that would * make the DB larger on disk potentially slowing it as well. * * 3) Loop through the dns_xfr database with a cursor to get * all the different hosts in a zone. Then use the zone & host * together to lookup the data in the dns_data database. YES - * This may slow down zone xfr's a little, but that's ok they * don't happen as often and don't need to be as fast. We can * also use this table when deleting a zone (The BDB driver * is read only - the delete would be used during replication * updates by a separate process). */ static isc_result_t bdbhpt_allnodes(const char *zone, void *driverarg, void *dbdata, dns_sdlzallnodes_t *allnodes) { isc_result_t result = ISC_R_NOTFOUND; bdbhpt_instance_t *db = (bdbhpt_instance_t *) dbdata; DBC *xfr_cursor = NULL; DBC *dns_cursor = NULL; DBT xfr_key, xfr_data, dns_key, dns_data; int xfr_flags; int dns_flags; int bdbhptres; bdbhpt_parsed_data_t pd; char *tmp = NULL, *tmp_zone, *tmp_zone_host = NULL; UNUSED(driverarg); memset(&xfr_key, 0, sizeof(DBT)); memset(&xfr_data, 0, sizeof(DBT)); memset(&dns_key, 0, sizeof(DBT)); memset(&dns_data, 0, sizeof(DBT)); xfr_key.data = tmp_zone = strdup(zone); if (xfr_key.data == NULL) return (ISC_R_NOMEMORY); xfr_key.size = strlen(xfr_key.data); /* get a cursor to loop through dns_xfr table */ if (db->xfr->cursor(db->xfr, NULL, &xfr_cursor, 0) != 0) { result = ISC_R_FAILURE; goto allnodes_cleanup; } /* get a cursor to loop through dns_data table */ if (db->data->cursor(db->data, NULL, &dns_cursor, 0) != 0) { result = ISC_R_FAILURE; goto allnodes_cleanup; } xfr_flags = DB_SET; /* loop through xfr table for specified zone. */ while ((bdbhptres = xfr_cursor->c_get(xfr_cursor, &xfr_key, &xfr_data, xfr_flags)) == 0) { xfr_flags = DB_NEXT_DUP; /* +1 to allow for space between zone and host names */ dns_key.size = xfr_data.size + xfr_key.size + 1; /* +1 to allow for null term at end of string. */ dns_key.data = tmp_zone_host = malloc(dns_key.size + 1); if (dns_key.data == NULL) goto allnodes_cleanup; /* * construct search key for dns_data. * zone_name(a space)host_name */ strcpy(dns_key.data, zone); strcat(dns_key.data, " "); strncat(dns_key.data, xfr_data.data, xfr_data.size); dns_flags = DB_SET; while ((bdbhptres = dns_cursor->c_get(dns_cursor, &dns_key, &dns_data, dns_flags)) == 0) { dns_flags = DB_NEXT_DUP; /* +1 to allow for null term at end of string. */ tmp = realloc(tmp, dns_data.size + 1); if (tmp == NULL) goto allnodes_cleanup; /* copy data to tmp string, and append null term. */ strncpy(tmp, dns_data.data, dns_data.size); tmp[dns_data.size] = '\0'; /* split string into dns data parts. */ if (bdbhpt_parse_data(tmp, &pd) != ISC_R_SUCCESS) goto allnodes_cleanup; result = dns_sdlz_putnamedrr(allnodes, pd.host, pd.type, pd.ttl, pd.data); if (result != ISC_R_SUCCESS) goto allnodes_cleanup; } /* end inner while loop */ /* clean up memory */ if (tmp_zone_host != NULL) { free(tmp_zone_host); tmp_zone_host = NULL; } } /* end outer while loop */ allnodes_cleanup: /* free any memory */ if (tmp != NULL) free(tmp); if (tmp_zone_host != NULL) free(tmp_zone_host); if (tmp_zone != NULL) free(tmp_zone); /* get rid of cursors */ if (xfr_cursor != NULL) xfr_cursor->c_close(xfr_cursor); if (dns_cursor != NULL) dns_cursor->c_close(dns_cursor); return result; } /*% * Performs bdbhpt cleanup. * Used by bdbhpt_create if there is an error starting up. * Used by bdbhpt_destroy when the driver is shutting down. */ static void bdbhpt_cleanup(bdbhpt_instance_t *db) { isc_mem_t *mctx; /* close databases */ if (db->data != NULL) db->data->close(db->data, 0); if (db->xfr != NULL) db->xfr->close(db->xfr, 0); if (db->zone != NULL) db->zone->close(db->zone, 0); if (db->client != NULL) db->client->close(db->client, 0); /* close environment */ if (db->dbenv != NULL) db->dbenv->close(db->dbenv, 0); /* cleanup memory */ if (db->mctx != NULL) { /* save mctx for later */ mctx = db->mctx; /* return, and detach the memory */ isc_mem_put(mctx, db, sizeof(bdbhpt_instance_t)); isc_mem_detach(&mctx); } } static isc_result_t bdbhpt_findzone(void *driverarg, void *dbdata, const char *name, dns_clientinfomethods_t *methods, dns_clientinfo_t *clientinfo) { isc_result_t result; bdbhpt_instance_t *db = (bdbhpt_instance_t *) dbdata; DBT key, data; UNUSED(driverarg); UNUSED(methods); UNUSED(clientinfo); memset(&key, 0, sizeof(DBT)); memset(&data, 0, sizeof(DBT)); data.flags = DB_DBT_MALLOC; key.data = strdup(name); if (key.data == NULL) return (ISC_R_NOMEMORY); /* * reverse string to take advantage of BDB locality of reference * if we need futher lookups because the zone doesn't match the * first time. */ key.data = bdbhpt_strrev(key.data); key.size = strlen(key.data); switch(db->zone->get(db->zone, NULL, &key, &data, 0)) { case DB_NOTFOUND: result = ISC_R_NOTFOUND; break; case 0: result = ISC_R_SUCCESS; break; default: result = ISC_R_FAILURE; } /* free any memory duplicate string in the key field */ if (key.data != NULL) free(key.data); /* free any memory allocated to the data field. */ if (data.data != NULL) free(data.data); return result; } static isc_result_t bdbhpt_lookup(const char *zone, const char *name, void *driverarg, void *dbdata, dns_sdlzlookup_t *lookup, dns_clientinfomethods_t *methods, dns_clientinfo_t *clientinfo) { isc_result_t result = ISC_R_NOTFOUND; bdbhpt_instance_t *db = (bdbhpt_instance_t *) dbdata; DBC *data_cursor = NULL; DBT key, data; int bdbhptres; int flags; bdbhpt_parsed_data_t pd; char *tmp = NULL; char *keyStr = NULL; UNUSED(driverarg); UNUSED(methods); UNUSED(clientinfo); memset(&key, 0, sizeof(DBT)); memset(&data, 0, sizeof(DBT)); key.size = strlen(zone) + strlen(name) + 1; /* allocate mem for key */ key.data = keyStr = malloc((key.size + 1) * sizeof(char)); if (keyStr == NULL) return ISC_R_NOMEMORY; strcpy(keyStr, zone); strcat(keyStr, " "); strcat(keyStr, name); /* get a cursor to loop through data */ if (db->data->cursor(db->data, NULL, &data_cursor, 0) != 0) { result = ISC_R_FAILURE; goto lookup_cleanup; } result = ISC_R_NOTFOUND; flags = DB_SET; while ((bdbhptres = data_cursor->c_get(data_cursor, &key, &data, flags)) == 0) { flags = DB_NEXT_DUP; tmp = realloc(tmp, data.size + 1); if (tmp == NULL) goto lookup_cleanup; strncpy(tmp, data.data, data.size); tmp[data.size] = '\0'; if (bdbhpt_parse_data(tmp, &pd) != ISC_R_SUCCESS) goto lookup_cleanup; result = dns_sdlz_putrr(lookup, pd.type, pd.ttl, pd.data); if (result != ISC_R_SUCCESS) goto lookup_cleanup; } /* end while loop */ lookup_cleanup: /* get rid of cursor */ if (data_cursor != NULL) data_cursor->c_close(data_cursor); if (keyStr != NULL) free(keyStr); if (tmp != NULL) free(tmp); return result; } /*% Initializes, sets flags and then opens Berkeley databases. */ static isc_result_t bdbhpt_opendb(DB_ENV *db_env, DBTYPE db_type, DB **db, const char *db_name, char *db_file, int flags) { int result; /* Initialize the database. */ if ((result = db_create(db, db_env, 0)) != 0) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, "bdbhpt could not initialize %s database. " "bdbhpt error: %s", db_name, db_strerror(result)); return ISC_R_FAILURE; } /* set database flags. */ if ((result = (*db)->set_flags(*db, flags)) != 0) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, "bdbhpt could not set flags for %s database. " "bdbhpt error: %s", db_name, db_strerror(result)); return ISC_R_FAILURE; } /* open the database. */ if ((result = (*db)->open(*db, NULL, db_file, db_name, db_type, DB_RDONLY | bdbhpt_threads, 0)) != 0) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, "bdbhpt could not open %s database in %s. " "bdbhpt error: %s", db_name, db_file, db_strerror(result)); return ISC_R_FAILURE; } return ISC_R_SUCCESS; } static isc_result_t bdbhpt_create(const char *dlzname, unsigned int argc, char *argv[], void *driverarg, void **dbdata) { isc_result_t result; int bdbhptres; int bdbFlags = 0; bdbhpt_instance_t *db = NULL; UNUSED(dlzname); UNUSED(driverarg); /* verify we have 4 arg's passed to the driver */ if (argc != 4) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, "bdbhpt driver requires at least " "3 command line args."); return (ISC_R_FAILURE); } switch((char) *argv[1]) { /* * Transactional mode. Highest safety - lowest speed. */ case 'T': case 't': bdbFlags = DB_INIT_MPOOL | DB_INIT_LOCK | DB_INIT_LOG | DB_INIT_TXN; isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(1), "bdbhpt driver using transactional mode."); break; /* * Concurrent mode. Lower safety (no rollback) - * higher speed. */ case 'C': case 'c': bdbFlags = DB_INIT_CDB | DB_INIT_MPOOL; isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(1), "bdbhpt driver using concurrent mode."); break; /* * Private mode. No inter-process communication & no locking. * Lowest saftey - highest speed. */ case 'P': case 'p': bdbFlags = DB_PRIVATE | DB_INIT_MPOOL; isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(1), "bdbhpt driver using private mode."); break; default: isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, "bdbhpt driver requires the operating mode " "be set to P or C or T. You specified '%s'", argv[1]); return (ISC_R_FAILURE); } /* allocate and zero memory for driver structure */ db = isc_mem_get(ns_g_mctx, sizeof(bdbhpt_instance_t)); if (db == NULL) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, "Could not allocate memory for " "database instance object."); return (ISC_R_NOMEMORY); } memset(db, 0, sizeof(bdbhpt_instance_t)); /* attach to the memory context */ isc_mem_attach(ns_g_mctx, &db->mctx); /* * create bdbhpt environment * Basically bdbhpt allocates and assigns memory to db->dbenv */ bdbhptres = db_env_create(&db->dbenv, 0); if (bdbhptres != 0) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, "bdbhpt environment could not be created. " "bdbhpt error: %s", db_strerror(bdbhptres)); result = ISC_R_FAILURE; goto init_cleanup; } /* open bdbhpt environment */ bdbhptres = db->dbenv->open(db->dbenv, argv[2], bdbFlags | bdbhpt_threads | DB_CREATE, 0); if (bdbhptres != 0) { isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, "bdbhpt environment at '%s' could not be opened." " bdbhpt error: %s", argv[2], db_strerror(bdbhptres)); result = ISC_R_FAILURE; goto init_cleanup; } /* open dlz_data database. */ result = bdbhpt_opendb(db->dbenv, DB_UNKNOWN, &db->data, dlz_data, argv[3], DB_DUP | DB_DUPSORT); if (result != ISC_R_SUCCESS) goto init_cleanup; /* open dlz_xfr database. */ result = bdbhpt_opendb(db->dbenv, DB_UNKNOWN, &db->xfr, dlz_xfr, argv[3], DB_DUP | DB_DUPSORT); if (result != ISC_R_SUCCESS) goto init_cleanup; /* open dlz_zone database. */ result = bdbhpt_opendb(db->dbenv, DB_UNKNOWN, &db->zone, dlz_zone, argv[3], 0); if (result != ISC_R_SUCCESS) goto init_cleanup; /* open dlz_client database. */ result = bdbhpt_opendb(db->dbenv, DB_UNKNOWN, &db->client, dlz_client, argv[3], DB_DUP | DB_DUPSORT); if (result != ISC_R_SUCCESS) goto init_cleanup; *dbdata = db; return(ISC_R_SUCCESS); init_cleanup: bdbhpt_cleanup(db); return result; } static void bdbhpt_destroy(void *driverarg, void *dbdata) { UNUSED(driverarg); bdbhpt_cleanup((bdbhpt_instance_t *) dbdata); } /* * bdbhpt_authority not needed as authority data is returned by lookup */ static dns_sdlzmethods_t dlz_bdbhpt_methods = { bdbhpt_create, bdbhpt_destroy, bdbhpt_findzone, bdbhpt_lookup, NULL, bdbhpt_allnodes, bdbhpt_allowzonexfr, NULL, NULL, NULL, NULL, NULL, NULL, NULL, }; /*% * Wrapper around dns_sdlzregister(). */ isc_result_t dlz_bdbhpt_init(void) { isc_result_t result; /* * Write debugging message to log */ isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2), "Registering DLZ bdbhpt driver."); result = dns_sdlzregister("bdbhpt", &dlz_bdbhpt_methods, NULL, DNS_SDLZFLAG_RELATIVEOWNER | DNS_SDLZFLAG_RELATIVERDATA | DNS_SDLZFLAG_THREADSAFE, ns_g_mctx, &dlz_bdbhpt); if (result != ISC_R_SUCCESS) { UNEXPECTED_ERROR(__FILE__, __LINE__, "dns_sdlzregister() failed: %s", isc_result_totext(result)); result = ISC_R_UNEXPECTED; } return result; } /*% * Wrapper around dns_sdlzunregister(). */ void dlz_bdbhpt_clear(void) { /* * Write debugging message to log */ isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2), "Unregistering DLZ bdbhpt driver."); if (dlz_bdbhpt != NULL) dns_sdlzunregister(&dlz_bdbhpt); } #endif