s4-dsdb: moved a bunch of fuctions from schema/schema_info_attr.c to samdb/ldb_modules/schema_util.c

these functions operate on ldb_modules, so they should be in the
ldb_modules directory. They also should return ldb errors codes, not
WERROR codes, as otherwise the error can be hidden from the ldap
caller

This re-arrangement fixes a dependency loop in the schema/samdb code.

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

3 files changed, 350 insertions, 10 deletions

diff --git a/source4/dsdb/samdb/ldb_modules/samldb.c b/source4/dsdb/samdb/ldb_modules/samldb.c
index 8db93b2a8a..21b6506fb9 100644
--- a/source4/dsdb/samdb/ldb_modules/samldb.c
+++ b/source4/dsdb/samdb/ldb_modules/samldb.c
@@ -706,7 +706,7 @@ static int samldb_fill_foreignSecurityPrincipal_object(struct samldb_ctx *ac)
 
 static int samldb_schema_info_update(struct samldb_ctx *ac)
 {
-	WERROR werr;
+	int ret;
 	struct ldb_context *ldb;
 	struct dsdb_schema *schema;
 
@@ -729,14 +729,11 @@ static int samldb_schema_info_update(struct samldb_ctx *ac)
 		return ldb_operr(ldb);
 	}
 
-	werr = dsdb_module_schema_info_update(ac->module, schema, DSDB_FLAG_NEXT_MODULE);
-	if (!W_ERROR_IS_OK(werr)) {
-		ldb_debug_set(ldb, LDB_DEBUG_FATAL,
-			      "samldb_schema_info_update: "
-		              "dsdb_module_schema_info_update failed with %s",
-		              win_errstr(werr));
-		DEBUG(0,(__location__ ": %s\n", ldb_errstring(ldb)));
-		return ldb_operr(ldb);
+	ret = dsdb_module_schema_info_update(ac->module, schema, DSDB_FLAG_NEXT_MODULE);
+	if (ret != LDB_SUCCESS) {
+		ldb_asprintf_errstring(ldb, "samldb_schema_info_update: dsdb_module_schema_info_update failed with %s",
+				       ldb_errstring(ldb));
+		return ret;
 	}
 
 	return LDB_SUCCESS;
diff --git a/source4/dsdb/samdb/ldb_modules/schema_util.c b/source4/dsdb/samdb/ldb_modules/schema_util.c
new file mode 100644
index 0000000000..79c0011c0c
--- /dev/null
+++ b/source4/dsdb/samdb/ldb_modules/schema_util.c
@@ -0,0 +1,337 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   dsdb module schema utility functions
+
+   Copyright (C) Kamen Mazdrashki <kamenim@samba.org> 2010
+   Copyright (C) Andrew Tridgell 2010
+   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2010
+
+   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 "dsdb/common/util.h"
+#include "dsdb/samdb/samdb.h"
+#include "dsdb/samdb/ldb_modules/util.h"
+#include "lib/ldb/include/ldb_module.h"
+#include "librpc/gen_ndr/ndr_drsuapi.h"
+#include "librpc/gen_ndr/ndr_drsblobs.h"
+#include "param/param.h"
+
+/**
+ * Reads schema_info structure from schemaInfo
+ * attribute on SCHEMA partition
+ *
+ * @param dsdb_flags 	DSDB_FLAG_... flag of 0
+ */
+int dsdb_module_schema_info_blob_read(struct ldb_module *ldb_module,
+				      uint32_t dsdb_flags,
+				      TALLOC_CTX *mem_ctx,
+				      struct ldb_val *schema_info_blob)
+{
+	int ldb_err;
+	const struct ldb_val *blob_val;
+	struct ldb_dn *schema_dn;
+	struct ldb_result *schema_res = NULL;
+	static const char *schema_attrs[] = {
+		"schemaInfo",
+		NULL
+	};
+
+	schema_dn = ldb_get_schema_basedn(ldb_module_get_ctx(ldb_module));
+	if (!schema_dn) {
+		DEBUG(0,("dsdb_module_schema_info_blob_read: no schema dn present!\n"));
+		return ldb_operr(ldb_module_get_ctx(ldb_module));
+	}
+
+	ldb_err = dsdb_module_search(ldb_module, mem_ctx, &schema_res, schema_dn,
+	                             LDB_SCOPE_BASE, schema_attrs, dsdb_flags, NULL);
+	if (ldb_err == LDB_ERR_NO_SUCH_OBJECT) {
+		DEBUG(0,("dsdb_module_schema_info_blob_read: Schema DN not found!\n"));
+		talloc_free(schema_res);
+		return ldb_err;
+	} else if (ldb_err != LDB_SUCCESS) {
+		DEBUG(0,("dsdb_module_schema_info_blob_read: failed to find schemaInfo attribute\n"));
+		talloc_free(schema_res);
+		return ldb_err;
+	}
+
+	blob_val = ldb_msg_find_ldb_val(schema_res->msgs[0], "schemaInfo");
+	if (!blob_val) {
+		DEBUG(0,("dsdb_module_schema_info_blob_read: no schemaInfo attribute found\n"));
+		talloc_free(schema_res);
+		return ldb_operr(ldb_module_get_ctx(ldb_module));
+	}
+
+	/* transfer .data ownership to mem_ctx */
+	schema_info_blob->length = blob_val->length;
+	schema_info_blob->data = talloc_steal(mem_ctx, blob_val->data);
+
+	talloc_free(schema_res);
+
+	return LDB_SUCCESS;
+}
+
+/**
+ * Prepares ldb_msg to be used for updating schemaInfo value in DB
+ */
+static int dsdb_schema_info_write_prepare(struct ldb_context *ldb,
+					  struct ldb_val *schema_info_blob,
+					  TALLOC_CTX *mem_ctx,
+					  struct ldb_message **_msg)
+{
+	int ldb_err;
+	struct ldb_message *msg;
+	struct ldb_dn *schema_dn;
+	struct ldb_message_element *return_el;
+
+	schema_dn = ldb_get_schema_basedn(ldb);
+	if (!schema_dn) {
+		DEBUG(0,("dsdb_schema_info_write_prepare: no schema dn present\n"));
+		return ldb_operr(ldb);
+	}
+
+	/* prepare ldb_msg to update schemaInfo */
+	msg = ldb_msg_new(mem_ctx);
+	if (msg == NULL) {
+		return ldb_oom(ldb);
+	}
+
+	msg->dn = schema_dn;
+	ldb_err = ldb_msg_add_value(msg, "schemaInfo", schema_info_blob, &return_el);
+	if (ldb_err != 0) {
+		ldb_asprintf_errstring(ldb, "dsdb_schema_info_write_prepare: ldb_msg_add_value failed - %s\n",
+				       ldb_strerror(ldb_err));
+		talloc_free(msg);
+		return ldb_err;
+	}
+
+	/* mark schemaInfo element for replacement */
+	return_el->flags = LDB_FLAG_MOD_REPLACE;
+
+	*_msg = msg;
+
+	return LDB_SUCCESS;
+}
+
+
+
+/**
+ * Writes schema_info structure into schemaInfo
+ * attribute on SCHEMA partition
+ *
+ * @param dsdb_flags 	DSDB_FLAG_... flag of 0
+ */
+int dsdb_module_schema_info_blob_write(struct ldb_module *ldb_module,
+				       uint32_t dsdb_flags,
+				       struct ldb_val *schema_info_blob)
+{
+	int ldb_err;
+	struct ldb_message *msg;
+	TALLOC_CTX *temp_ctx;
+
+	temp_ctx = talloc_new(ldb_module);
+	if (temp_ctx == NULL) {
+		return ldb_module_oom(ldb_module);
+	}
+
+	/* write serialized schemaInfo into LDB */
+	ldb_err = dsdb_schema_info_write_prepare(ldb_module_get_ctx(ldb_module),
+						 schema_info_blob,
+						 temp_ctx, &msg);
+	if (ldb_err != LDB_SUCCESS) {
+		talloc_free(temp_ctx);
+		return ldb_err;
+	}
+
+
+	ldb_err = dsdb_module_modify(ldb_module, msg, dsdb_flags);
+
+	talloc_free(temp_ctx);
+
+	if (ldb_err != LDB_SUCCESS) {
+		ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module),
+				       "dsdb_module_schema_info_blob_write: dsdb_replace failed: %s (%s)\n",
+				       ldb_strerror(ldb_err),
+				       ldb_errstring(ldb_module_get_ctx(ldb_module)));
+		return ldb_err;
+	}
+
+	return LDB_SUCCESS;
+}
+
+
+/**
+ * Reads schema_info structure from schemaInfo
+ * attribute on SCHEMA partition
+ */
+static int dsdb_module_schema_info_read(struct ldb_module *ldb_module,
+					uint32_t dsdb_flags,
+					TALLOC_CTX *mem_ctx,
+					struct dsdb_schema_info **_schema_info)
+{
+	int ret;
+	DATA_BLOB ndr_blob;
+	TALLOC_CTX *temp_ctx;
+	WERROR werr;
+
+	temp_ctx = talloc_new(mem_ctx);
+	if (temp_ctx == NULL) {
+		return ldb_module_oom(ldb_module);
+	}
+
+	/* read serialized schemaInfo from LDB  */
+	ret = dsdb_module_schema_info_blob_read(ldb_module, dsdb_flags, temp_ctx, &ndr_blob);
+	if (ret != LDB_SUCCESS) {
+		talloc_free(temp_ctx);
+		return ret;
+	}
+
+	/* convert NDR blob to dsdb_schema_info object */
+	werr = dsdb_schema_info_from_blob(&ndr_blob,
+					  mem_ctx,
+					  _schema_info);
+	talloc_free(temp_ctx);
+
+	if (W_ERROR_EQUAL(werr, WERR_DS_NO_ATTRIBUTE_OR_VALUE)) {
+		return LDB_ERR_NO_SUCH_ATTRIBUTE;
+	}
+
+	if (!W_ERROR_IS_OK(werr)) {
+		ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module), __location__ ": failed to get schema_info");
+		return ldb_operr(ldb_module_get_ctx(ldb_module));
+	}
+
+	return LDB_SUCCESS;
+}
+
+/**
+ * Writes schema_info structure into schemaInfo
+ * attribute on SCHEMA partition
+ *
+ * @param dsdb_flags 	DSDB_FLAG_... flag of 0
+ */
+static int dsdb_module_schema_info_write(struct ldb_module *ldb_module,
+					 uint32_t dsdb_flags,
+					 const struct dsdb_schema_info *schema_info)
+{
+	WERROR werr;
+	int ret;
+	DATA_BLOB ndr_blob;
+	TALLOC_CTX *temp_ctx;
+
+	temp_ctx = talloc_new(ldb_module);
+	if (temp_ctx == NULL) {
+		return ldb_module_oom(temp_ctx);
+	}
+
+	/* convert schema_info to a blob */
+	werr = dsdb_blob_from_schema_info(schema_info, temp_ctx, &ndr_blob);
+	if (!W_ERROR_IS_OK(werr)) {
+		talloc_free(temp_ctx);
+		ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module), __location__ ": failed to get schema_info");
+		return ldb_operr(ldb_module_get_ctx(ldb_module));
+	}
+
+	/* write serialized schemaInfo into LDB */
+	ret = dsdb_module_schema_info_blob_write(ldb_module, dsdb_flags, &ndr_blob);
+
+	talloc_free(temp_ctx);
+
+	return ret;
+}
+
+
+/**
+ * Increments schemaInfo revision and save it to DB
+ * setting our invocationID in the process
+ * NOTE: this function should be called in a transaction
+ * much in the same way prefixMap update function is called
+ *
+ * @param ldb_module 	current module
+ * @param schema 	schema cache
+ * @param dsdb_flags 	DSDB_FLAG_... flag of 0
+ */
+int dsdb_module_schema_info_update(struct ldb_module *ldb_module,
+				   struct dsdb_schema *schema,
+				   int dsdb_flags)
+{
+	int ret;
+	const struct GUID *invocation_id;
+	DATA_BLOB ndr_blob;
+	struct dsdb_schema_info *schema_info;
+	const char *schema_info_str;
+	WERROR werr;
+	TALLOC_CTX *temp_ctx = talloc_new(schema);
+	if (temp_ctx == NULL) {
+		return ldb_module_oom(ldb_module);
+	}
+
+	invocation_id = samdb_ntds_invocation_id(ldb_module_get_ctx(ldb_module));
+	if (!invocation_id) {
+		talloc_free(temp_ctx);
+		return ldb_operr(ldb_module_get_ctx(ldb_module));
+	}
+
+	/* read serialized schemaInfo from LDB  */
+	ret = dsdb_module_schema_info_read(ldb_module, dsdb_flags, temp_ctx, &schema_info);
+	if (ret == LDB_ERR_NO_SUCH_ATTRIBUTE) {
+		/* make default value in case
+		 * we have no schemaInfo value yet */
+		werr = dsdb_schema_info_new(temp_ctx, &schema_info);
+		if (!W_ERROR_IS_OK(werr)) {
+			talloc_free(temp_ctx);
+			return ldb_module_oom(ldb_module);
+		}
+		ret = LDB_SUCCESS;
+	}
+	if (ret != LDB_SUCCESS) {
+		talloc_free(temp_ctx);
+		return ret;
+	}
+
+	/* update schemaInfo */
+	schema_info->revision++;
+	schema_info->invocation_id = *invocation_id;
+
+	ret = dsdb_module_schema_info_write(ldb_module, dsdb_flags, schema_info);
+	if (ret != LDB_SUCCESS) {
+		ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module),
+				       "dsdb_module_schema_info_update: failed to save schemaInfo - %s\n",
+				       ldb_strerror(ret));
+		talloc_free(temp_ctx);
+		return ret;
+	}
+
+	/* finally, update schema_info in the cache */
+	werr = dsdb_blob_from_schema_info(schema_info, temp_ctx, &ndr_blob);
+	if (!W_ERROR_IS_OK(werr)) {
+		ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module), "Failed to get schema info");
+		talloc_free(temp_ctx);
+		return ldb_operr(ldb_module_get_ctx(ldb_module));
+	}
+
+	schema_info_str = hex_encode_talloc(schema, ndr_blob.data, ndr_blob.length);
+	if (!schema_info_str) {
+		talloc_free(temp_ctx);
+		return ldb_module_oom(ldb_module);
+	}
+
+	talloc_unlink(schema, discard_const(schema->schema_info));
+	schema->schema_info = schema_info_str;
+
+	talloc_free(temp_ctx);
+	return LDB_SUCCESS;
+}
diff --git a/source4/dsdb/samdb/ldb_modules/wscript_build b/source4/dsdb/samdb/ldb_modules/wscript_build
index e6f6956163..79d93ccef8 100644
--- a/source4/dsdb/samdb/ldb_modules/wscript_build
+++ b/source4/dsdb/samdb/ldb_modules/wscript_build
@@ -1,7 +1,13 @@
 #!/usr/bin/env python
 
+bld.SAMBA_LIBRARY('DSDB_MODULE',
+                  source=[],
+                  deps='DSDB_MODULE_HELPERS DSDB_MODULE_HELPER_SCHEMA DSDB_MODULE_HELPER_RIDALLOC',
+                  private_library=True,
+                  grouping_library=True)
+
 bld.SAMBA_SUBSYSTEM('DSDB_MODULE_HELPERS',
-	source='util.c acl_util.c',
+	source='util.c acl_util.c schema_util.c',
 	autoproto='util_proto.h',
 	deps='ldb LIBNDR SAMDB_COMMON LIBSECURITY_SESSION'
 	)