BIND 9.11: Port to new dyndb API.

This is first step which allows the plugin to run.
It requires configuration in format
dyndb <name> <library> {
	{option1 value}
	{option2 value}
};

This will be improved in another patch.

README

@@ -2,15 +2,9 @@
 ===============
 
 The dynamic LDAP back-end is a plug-in for BIND that provides an LDAP
-database back-end capabilities. For now, it requires that BIND is patched
-to support dynamic loading of database back-ends. You can get a patch
-for your version here:
+database back-end capabilities. It requires dyndb interface which is present
+in BIND versions >= 9.11.0rc1.
 
-  https://github.com/pspacek/bind-dynamic_db
-
-Hopefully, the patch will once be included in the official BIND release.
-
-BIND >= 9.9.0 is required.
 
 2. Features
 ===========
@@ -309,19 +303,17 @@ Attributes:
 5. Configuration
 ================
 
-To configure dynamic loading of back-end, you must put a "dynamic-db"
+To configure dynamic loading of back-end, you must put a "dyndb"
 clause into your named.conf. The clause must then be followed by a
-string denoting the name. The name is not that much important, it is
-passed to the plug-in and might be used for example, for logging
-purposes. Following after that is a set of options enclosed between
-curly brackets.
+string denoting the name of the instance and path to dyndb library.
 
-The most important option here is "library". It names a shared object
-file that will be opened and loaded. The "arg" option specifies a string
-that is passed directly to the plugin. You can specify multiple "arg"
-options. The LDAP back-end follows the convention that the first word of
-this string is the name of the setting and the rest is the value.
+The name is not that much important, it is passed to the plug-in
+and is used for logging purposes and for naming working directories.
 
+Library path must point to a shared object file that will be opened and loaded.
+
+Name and library path have to be followed by set of options enclosed between
+curly brackets.
 
 5.1 Configuration options
 -------------------------

configure.ac

@@ -3,7 +3,7 @@ AC_INIT([bind-dyndb-ldap], [10.1], [[email protected]])
 
 AM_INIT_AUTOMAKE([-Wall foreign dist-bzip2])
 
-AC_CONFIG_SRCDIR([src/zone_manager.h])
+AC_CONFIG_SRCDIR([src/ldap_driver.c])
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_MACRO_DIR([m4])
 

src/Makefile.am

@@ -26,7 +26,6 @@ HDRS =				\
 	types.h			\
 	util.h			\
 	zone.h			\
-	zone_manager.h		\
 	zone_register.h
 
 ldap_la_SOURCES =		\
@@ -53,7 +52,6 @@ ldap_la_SOURCES =		\
 	syncrepl.c		\
 	str.c			\
 	zone.c			\
-	zone_manager.c		\
 	zone_register.c
 
 ldap_la_CFLAGS = -Wall -Wextra @WERROR@ -std=gnu99 -O2

src/ldap_driver.c

@@ -9,13 +9,17 @@
 #endif
 
 #include <isc/buffer.h>
+#include <isc/commandline.h>
+#include <isc/hash.h>
+#include <isc/lib.h>
 #include <isc/mem.h>
+#include <isc/once.h>
 #include <isc/refcount.h>
 #include <isc/util.h>
 
 #include <dns/db.h>
 #include <dns/diff.h>
-#include <dns/dynamic_db.h>
+#include <dns/dyndb.h>
 #include <dns/dbiterator.h>
 #include <dns/rdata.h>
 #include <dns/rdataclass.h>
@@ -29,12 +33,12 @@
 
 #include <string.h> /* For memcpy */
 
+#include "bindcfg.h"
 #include "ldap_driver.h"
 #include "ldap_helper.h"
 #include "ldap_convert.h"
 #include "log.h"
 #include "util.h"
-#include "zone_manager.h"
 #include "zone_register.h"
 
 #ifdef HAVE_VISIBILITY
@@ -918,18 +922,17 @@ ldapdb_associate(isc_mem_t *mctx, dns_name_t *name, dns_dbtype_t type,
 		 void *driverarg, dns_db_t **dbp) {
 
 	isc_result_t result;
-	ldap_instance_t *ldap_inst = NULL;
+	ldap_instance_t *ldap_inst = driverarg;
 	zone_register_t *zr = NULL;
 
-	UNUSED(driverarg); /* Currently we don't need any data */
-
 	REQUIRE(ISCAPI_MCTX_VALID(mctx));
-	REQUIRE(argc == LDAP_DB_ARGC);
 	REQUIRE(type == LDAP_DB_TYPE);
 	REQUIRE(rdclass == LDAP_DB_RDATACLASS);
+	REQUIRE(argc == 0);
+	UNUSED(argv);
+	REQUIRE(driverarg != NULL);
 	REQUIRE(dbp != NULL && *dbp == NULL);
 
-	CHECK(manager_get_ldap_instance(argv[0], &ldap_inst));
 	zr = ldap_instance_getzr(ldap_inst);
 	if (zr == NULL)
 		CLEANUP_WITH(ISC_R_NOTFOUND);
@@ -942,19 +945,16 @@ ldapdb_associate(isc_mem_t *mctx, dns_name_t *name, dns_dbtype_t type,
 
 isc_result_t
 ldapdb_create(isc_mem_t *mctx, dns_name_t *name, dns_dbtype_t type,
-	      dns_rdataclass_t rdclass, unsigned int argc, char *argv[],
-	      void *driverarg, dns_db_t **dbp)
+	      dns_rdataclass_t rdclass, void *driverarg, dns_db_t **dbp)
 {
 	ldapdb_t *ldapdb = NULL;
 	isc_result_t result;
 	isc_boolean_t lock_ready = ISC_FALSE;
 
-	UNUSED(driverarg); /* Currently we don't need any data */
-
 	/* Database instance name. */
-	REQUIRE(argc == LDAP_DB_ARGC);
 	REQUIRE(type == LDAP_DB_TYPE);
 	REQUIRE(rdclass == LDAP_DB_RDATACLASS);
+	REQUIRE(driverarg != NULL);
 	REQUIRE(dbp != NULL && *dbp == NULL);
 
 	CHECKED_MEM_GET_PTR(mctx, ldapdb);
@@ -976,7 +976,7 @@ ldapdb_create(isc_mem_t *mctx, dns_name_t *name, dns_dbtype_t type,
 	CHECK(dns_name_dupwithoffsets(name, mctx, &ldapdb->common.origin));
 
 	CHECK(isc_refcount_init(&ldapdb->refs, 1));
-	CHECK(manager_get_ldap_instance(argv[0], &ldapdb->ldap_inst));
+	ldapdb->ldap_inst = driverarg;
 
 	CHECK(dns_db_create(mctx, "rbt", name, dns_dbtype_zone,
 			    dns_rdataclass_in, 0, NULL, &ldapdb->rbtdb));
@@ -1000,50 +1000,105 @@ ldapdb_create(isc_mem_t *mctx, dns_name_t *name, dns_dbtype_t type,
 	return result;
 }
 
-static dns_dbimplementation_t *ldapdb_imp;
-const char *ldapdb_impname = "dynamic-ldap";
+static void
+library_init(void)
+{
+       log_info("bind-dyndb-ldap version " VERSION
+                " compiled at " __TIME__ " " __DATE__
+                ", compiler " __VERSION__);
+       cfg_init_types();
+}
+
+/*
+ * Driver version is called when loading the driver to ensure there
+ * is no API mismatch betwen the driver and the caller.
+ */
+VISIBLE int
+dyndb_version(unsigned int *flags) {
+	UNUSED(flags);
 
+	return (DNS_DYNDB_VERSION);
+}
 
+/*
+ * Driver init is called for each dyndb section in named.conf
+ * once during startup and then again on every reload.
+ *
+ * @code
+ * dyndb example-name "sample.so" { param1 param2 };
+ * @endcode
+ *
+ * @param[in] name        User-defined string from dyndb "name" {}; definition
+ *                        in named.conf.
+ *                        The example above will have name = "example-name".
+ * @param[in] parameters  User-defined parameters from dyndb section as one
+ *                        string. The example above will have
+ *                        params = "param1 param2";
+ * @param[out] instp      Pointer to instance-specific data
+ *                        (for one dyndb section).
+ */
 VISIBLE isc_result_t
-dynamic_driver_init(isc_mem_t *mctx, const char *name, const char * const *argv,
-		    dns_dyndb_arguments_t *dyndb_args)
+dyndb_init(isc_mem_t *mctx, const char *name, const char *parameters,
+	   const char *file, unsigned long line, const dns_dyndbctx_t *dctx,
+	   void **instp)
 {
-	dns_dbimplementation_t *ldapdb_imp_new = NULL;
+	unsigned int argc;
+	char **argv = NULL;
+	char *tmps = NULL;
+	ldap_instance_t *inst = NULL;
 	isc_result_t result;
+	static isc_once_t library_init_once = ISC_ONCE_INIT;
 
 	REQUIRE(name != NULL);
-	REQUIRE(argv != NULL);
-	REQUIRE(dyndb_args != NULL);
+	REQUIRE(parameters != NULL);
+	REQUIRE(dctx != NULL);
+	REQUIRE(instp != NULL && *instp == NULL);
 
-	log_debug(2, "registering dynamic ldap driver for %s.", name);
+	RUNTIME_CHECK(isc_once_do(&library_init_once, library_init)
+		      == ISC_R_SUCCESS);
 
 	/*
-	 * We need to discover what rdataset methods does
-	 * dns_rdatalist_tordataset use. We then make a copy for ourselves
-	 * with the exception that we modify the disassociate method to free
-	 * the rdlist we allocate for it in clone_rdatalist_to_rdataset().
+	 * Depending on how dlopen() was called, we may not have
+	 * access to named's global namespace, in which case we need
+	 * to initialize libisc/libdns
 	 */
+	if (dctx->refvar != &isc_bind9) {
+		isc_lib_register();
+		isc_log_setcontext(dctx->lctx);
+		dns_log_setcontext(dctx->lctx);
+	}
 
-	/* Register new DNS DB implementation. */
-	result = dns_db_register(ldapdb_impname, &ldapdb_associate, NULL, mctx,
-				 &ldapdb_imp_new);
-	if (result != ISC_R_SUCCESS && result != ISC_R_EXISTS)
-		return result;
-	else if (result == ISC_R_SUCCESS)
-		ldapdb_imp = ldapdb_imp_new;
+	isc_hash_set_initializer(dctx->hashinit);
+
+	log_debug(2, "registering dynamic ldap driver for %s.", name);
+
+	tmps = isc_mem_strdup(mctx, parameters);
+	if (tmps == NULL) {
+		result = ISC_R_NOMEMORY;
+		goto cleanup;
+	}
+	CHECK(isc_commandline_strtoargv(mctx, tmps, &argc, &argv, 0));
 
 	/* Finally, create the instance. */
-	result = manager_create_db_instance(mctx, name, argv, dyndb_args);
+	CHECK(new_ldap_instance(mctx, name, argc, argv, dctx, &inst));
+	*instp = inst;
+
+cleanup:
+	if (tmps != NULL)
+		isc_mem_free(mctx, tmps);
+	if (argv != NULL)
+		isc_mem_put(mctx, argv, argc * sizeof(*argv));
 
 	return result;
 }
 
+/*
+ * Driver destroy is called for every instance on every reload and then once
+ * during shutdown.
+ *
+ * @param[out] instp Pointer to instance-specific data (for one dyndb section).
+ */
 VISIBLE void
-dynamic_driver_destroy(void)
-{
-	/* Only unregister the implementation if it was registered by us. */
-	if (ldapdb_imp != NULL)
-		dns_db_unregister(&ldapdb_imp);
-
-	destroy_manager();
+dyndb_destroy(void **instp) {
+	destroy_ldap_instance((ldap_instance_t **)instp);
 }

src/ldap_driver.h

@@ -19,9 +19,13 @@ typedef struct ldapdb ldapdb_t;
 
 isc_result_t
 ldapdb_create(isc_mem_t *mctx, dns_name_t *name, dns_dbtype_t type,
-	      dns_rdataclass_t rdclass, unsigned int argc, char *argv[],
-	      void *driverarg, dns_db_t **dbp) ATTR_NONNULL(1,2,6,8);
+	      dns_rdataclass_t rdclass, void *driverarg, dns_db_t **dbp)
+	      ATTR_NONNULL(1,2,5,6);
 
+isc_result_t
+ldapdb_associate(isc_mem_t *mctx, dns_name_t *name, dns_dbtype_t type,
+		 dns_rdataclass_t rdclass, unsigned int argc, char *argv[],
+		 void *driverarg, dns_db_t **dbp) ATTR_NONNULL(1,2,7,8);
 dns_db_t *
 ldapdb_get_rbtdb(dns_db_t *db) ATTR_NONNULLS;