s4-dsdb: calculate validFSMOs at runtime instead of pre-computing

this changes the rootdse to compute the validFSMOs attribute at
runtime by checking the fSMORoleOwner attribute on the appropriate
DN. This avoids the need for the pdc_fsmo and naming_fsmo modules.

Pair-Programmed-With: Andrew Bartlett <abartlet@samba.org>

3 files changed, 45 insertions, 251 deletions

diff --git a/source4/dsdb/samdb/ldb_modules/naming_fsmo.c b/source4/dsdb/samdb/ldb_modules/naming_fsmo.c
deleted file mode 100644
index f59919ca1a..0000000000
--- a/source4/dsdb/samdb/ldb_modules/naming_fsmo.c
+++ /dev/null
@@ -1,108 +0,0 @@
-/* 
-   Unix SMB/CIFS mplementation.
-
-   The module that handles the Domain Naming FSMO Role Owner
-   checkings
-   
-   Copyright (C) Stefan Metzmacher 2007
-    
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-   
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-   
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.
-   
-*/
-
-#include "includes.h"
-#include "ldb_module.h"
-#include "dsdb/samdb/samdb.h"
-#include "librpc/gen_ndr/ndr_misc.h"
-#include "librpc/gen_ndr/ndr_drsuapi.h"
-#include "librpc/gen_ndr/ndr_drsblobs.h"
-#include "../lib/util/dlinklist.h"
-#include "dsdb/samdb/ldb_modules/util.h"
-
-static int naming_fsmo_init(struct ldb_module *module)
-{
-	struct ldb_context *ldb;
-	TALLOC_CTX *mem_ctx;
-	struct ldb_dn *naming_dn;
-	struct dsdb_naming_fsmo *naming_fsmo;
-	struct ldb_result *naming_res;
-	int ret;
-	static const char *naming_attrs[] = {
-		"fSMORoleOwner",
-		NULL
-	};
-
-	ldb = ldb_module_get_ctx(module);
-
-	mem_ctx = talloc_new(module);
-	if (!mem_ctx) {
-		return ldb_oom(ldb);
-	}
-
-	naming_dn = samdb_partitions_dn(ldb, mem_ctx);
-	if (!naming_dn) {
-		ldb_debug_set(ldb, LDB_DEBUG_FATAL,
-			      "naming_fsmo_init: unable to determine partitions dn");
-		talloc_free(mem_ctx);
-		return LDB_ERR_OPERATIONS_ERROR;
-	}
-
-	naming_fsmo = talloc_zero(mem_ctx, struct dsdb_naming_fsmo);
-	if (!naming_fsmo) {
-		return ldb_oom(ldb);
-	}
-	ldb_module_set_private(module, naming_fsmo);
-
-	ret = dsdb_module_search_dn(module, mem_ctx, &naming_res,
-				    naming_dn,
-				    naming_attrs,
-				    DSDB_FLAG_NEXT_MODULE, NULL);
-	if (ret == LDB_ERR_NO_SUCH_OBJECT) {
-		ldb_debug(ldb, LDB_DEBUG_TRACE,
-			  "naming_fsmo_init: no partitions dn present: (skip loading of naming contexts details)");
-		talloc_free(mem_ctx);
-		return ldb_next_init(module);
-	}
-
-	naming_fsmo->master_dn = ldb_msg_find_attr_as_dn(ldb, naming_fsmo, naming_res->msgs[0], "fSMORoleOwner");
-	if (ldb_dn_compare(samdb_ntds_settings_dn(ldb), naming_fsmo->master_dn) == 0) {
-		naming_fsmo->we_are_master = true;
-	} else {
-		naming_fsmo->we_are_master = false;
-	}
-
-	if (ldb_set_opaque(ldb, "dsdb_naming_fsmo", naming_fsmo) != LDB_SUCCESS) {
-		return ldb_oom(ldb);
-	}
-
-	talloc_steal(module, naming_fsmo);
-
-	ldb_debug(ldb, LDB_DEBUG_TRACE,
-			  "naming_fsmo_init: we are master: %s\n",
-			  (naming_fsmo->we_are_master?"yes":"no"));
-
-	talloc_free(mem_ctx);
-	return ldb_next_init(module);
-}
-
-static const struct ldb_module_ops ldb_naming_fsmo_module_ops = {
-	.name		= "naming_fsmo",
-	.init_context	= naming_fsmo_init
-};
-
-int ldb_naming_fsmo_module_init(const char *version)
-{
-	LDB_MODULE_CHECK_VERSION(version);
-	return ldb_register_module(&ldb_naming_fsmo_module_ops);
-}
diff --git a/source4/dsdb/samdb/ldb_modules/pdc_fsmo.c b/source4/dsdb/samdb/ldb_modules/pdc_fsmo.c
deleted file mode 100644
index 68f181581c..0000000000
--- a/source4/dsdb/samdb/ldb_modules/pdc_fsmo.c
+++ /dev/null
@@ -1,113 +0,0 @@
-/* 
-   Unix SMB/CIFS mplementation.
-
-   The module that handles the PDC FSMO Role Owner checkings
-   
-   Copyright (C) Stefan Metzmacher 2007
-    
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-   
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-   
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.
-   
-*/
-
-#include "includes.h"
-#include "ldb_module.h"
-#include "dsdb/samdb/samdb.h"
-#include "librpc/gen_ndr/ndr_misc.h"
-#include "librpc/gen_ndr/ndr_drsuapi.h"
-#include "librpc/gen_ndr/ndr_drsblobs.h"
-#include "../lib/util/dlinklist.h"
-#include "dsdb/samdb/ldb_modules/util.h"
-
-static int pdc_fsmo_init(struct ldb_module *module)
-{
-	struct ldb_context *ldb;
-	TALLOC_CTX *mem_ctx;
-	struct ldb_dn *pdc_dn;
-	struct dsdb_pdc_fsmo *pdc_fsmo;
-	struct ldb_result *pdc_res;
-	int ret;
-	static const char *pdc_attrs[] = {
-		"fSMORoleOwner",
-		NULL
-	};
-
-	ldb = ldb_module_get_ctx(module);
-
-	mem_ctx = talloc_new(module);
-	if (!mem_ctx) {
-		return ldb_oom(ldb);
-	}
-
-	pdc_dn = ldb_get_default_basedn(ldb);
-	if (!pdc_dn) {
-		ldb_debug_set(ldb, LDB_DEBUG_FATAL,
-			  "pdc_fsmo_init: could not determine default basedn");
-		talloc_free(mem_ctx);
-		return LDB_ERR_OPERATIONS_ERROR;
-	}
-
-	pdc_fsmo = talloc_zero(mem_ctx, struct dsdb_pdc_fsmo);
-	if (!pdc_fsmo) {
-		return ldb_oom(ldb);
-	}
-	ldb_module_set_private(module, pdc_fsmo);
-
-	ret = dsdb_module_search_dn(module, mem_ctx, &pdc_res,
-				    pdc_dn, 
-				    pdc_attrs,
-				    DSDB_FLAG_NEXT_MODULE, NULL);
-	if (ret == LDB_ERR_NO_SUCH_OBJECT) {
-		ldb_debug(ldb, LDB_DEBUG_TRACE,
-			  "pdc_fsmo_init: no domain object present: (skip loading of domain details)");
-		talloc_free(mem_ctx);
-		return ldb_next_init(module);
-	} else if (ret != LDB_SUCCESS) {
-		ldb_debug_set(ldb, LDB_DEBUG_FATAL,
-			      "pdc_fsmo_init: failed to search the domain object: %d:%s: %s",
-			      ret, ldb_strerror(ret), ldb_errstring(ldb));
-		talloc_free(mem_ctx);
-		return ret;
-	}
-
-	pdc_fsmo->master_dn = ldb_msg_find_attr_as_dn(ldb, mem_ctx, pdc_res->msgs[0], "fSMORoleOwner");
-	if (ldb_dn_compare(samdb_ntds_settings_dn(ldb), pdc_fsmo->master_dn) == 0) {
-		pdc_fsmo->we_are_master = true;
-	} else {
-		pdc_fsmo->we_are_master = false;
-	}
-
-	if (ldb_set_opaque(ldb, "dsdb_pdc_fsmo", pdc_fsmo) != LDB_SUCCESS) {
-		return ldb_oom(ldb);
-	}
-
-	talloc_steal(module, pdc_fsmo);
-
-	ldb_debug(ldb, LDB_DEBUG_TRACE,
-			  "pdc_fsmo_init: we are master: %s\n",
-			  (pdc_fsmo->we_are_master?"yes":"no"));
-
-	talloc_free(mem_ctx);
-	return ldb_next_init(module);
-}
-
-static const struct ldb_module_ops ldb_pdc_fsmo_module_ops = {
-	.name		= "pdc_fsmo",
-	.init_context	= pdc_fsmo_init
-};
-
-int ldb_pdc_fsmo_module_init(const char *version)
-{
-	LDB_MODULE_CHECK_VERSION(version);
-	return ldb_register_module(&ldb_pdc_fsmo_module_ops);
-}
diff --git a/source4/dsdb/samdb/ldb_modules/rootdse.c b/source4/dsdb/samdb/ldb_modules/rootdse.c
index 2499e82ad3..cfd75e8c43 100644
--- a/source4/dsdb/samdb/ldb_modules/rootdse.c
+++ b/source4/dsdb/samdb/ldb_modules/rootdse.c
@@ -170,6 +170,37 @@ static int expand_dn_in_message(struct ldb_module *module, struct ldb_message *m
 	return LDB_SUCCESS;
 }
 
+/*
+  see if we are master for a FSMO role
+ */
+static int dsdb_module_we_are_master(struct ldb_module *module, struct ldb_dn *dn, bool *master,
+				     struct ldb_request *parent)
+{
+	const char *attrs[] = { "fSMORoleOwner", NULL };
+	TALLOC_CTX *tmp_ctx = talloc_new(parent);
+	struct ldb_result *res;
+	int ret;
+	struct ldb_dn *owner_dn;
+
+	ret = dsdb_module_search_dn(module, tmp_ctx, &res,
+				    dn, attrs, DSDB_FLAG_NEXT_MODULE, parent);
+	if (ret != LDB_SUCCESS) {
+		talloc_free(tmp_ctx);
+		return ret;
+	}
+
+	owner_dn = ldb_msg_find_attr_as_dn(ldb_module_get_ctx(module),
+					   tmp_ctx, res->msgs[0], "fSMORoleOwner");
+	if (!owner_dn) {
+		*master = false;
+		talloc_free(tmp_ctx);
+		return LDB_SUCCESS;
+	}
+
+	*master = (ldb_dn_compare(owner_dn, samdb_ntds_settings_dn(ldb_module_get_ctx(module))) == 0);
+	talloc_free(tmp_ctx);
+	return LDB_SUCCESS;
+}
 
 /*
   add dynamically generated attributes to rootDSE result
@@ -190,6 +221,7 @@ static int rootdse_add_dynamic(struct ldb_module *module, struct ldb_message *ms
 		"rootDomainNamingContext",
 		"schemaNamingContext",
 		"serverName",
+		"validFSMOs",
 		NULL
 	};
 
@@ -346,38 +378,21 @@ static int rootdse_add_dynamic(struct ldb_module *module, struct ldb_message *ms
 	}
 
 	if (do_attribute_explicit(attrs, "validFSMOs")) {
-		const struct dsdb_naming_fsmo *naming_fsmo;
-		const struct dsdb_pdc_fsmo *pdc_fsmo;
-		const char *dn_str;
-
-		if (schema && schema->fsmo.we_are_master) {
-			dn_str = ldb_dn_get_linearized(ldb_get_schema_basedn(ldb));
-			if (dn_str && dn_str[0]) {
-				if (ldb_msg_add_fmt(msg, "validFSMOs", "%s", dn_str) != LDB_SUCCESS) {
-					goto failed;
-				}
-			}
-		}
+		struct ldb_dn *dns[3];
 
-		naming_fsmo = talloc_get_type(ldb_get_opaque(ldb, "dsdb_naming_fsmo"),
-					      struct dsdb_naming_fsmo);
-		if (naming_fsmo && naming_fsmo->we_are_master) {
-			dn_str = ldb_dn_get_linearized(samdb_partitions_dn(ldb, msg));
-			if (dn_str && dn_str[0]) {
-				if (ldb_msg_add_fmt(msg, "validFSMOs", "%s", dn_str) != LDB_SUCCESS) {
-					goto failed;
-				}
-			}
-		}
+		dns[0] = ldb_get_schema_basedn(ldb);
+		dns[1] = samdb_partitions_dn(ldb, msg);
+		dns[2] = ldb_get_default_basedn(ldb);
 
-		pdc_fsmo = talloc_get_type(ldb_get_opaque(ldb, "dsdb_pdc_fsmo"),
-					   struct dsdb_pdc_fsmo);
-		if (pdc_fsmo && pdc_fsmo->we_are_master) {
-			dn_str = ldb_dn_get_linearized(ldb_get_default_basedn(ldb));
-			if (dn_str && dn_str[0]) {
-				if (ldb_msg_add_fmt(msg, "validFSMOs", "%s", dn_str) != LDB_SUCCESS) {
-					goto failed;
-				}
+		for (i=0; i<3; i++) {
+			bool master;
+			int ret = dsdb_module_we_are_master(module, dns[i], &master, req);
+			if (ret != LDB_SUCCESS) {
+				goto failed;
+			}
+			if (master && ldb_msg_add_fmt(msg, "validFSMOs", "%s",
+						      ldb_dn_get_linearized(dns[i])) != LDB_SUCCESS) {
+				goto failed;
 			}
 		}
 	}