dsdb: refactor part of garbage_collect_tombstones into new function

Pair-programmed-with: Garming Sam <garming@catalyst.net.nz>

Signed-off-by: Bob Campbell <bobcampbell@catalyst.net.nz>
Signed-off-by: Garming Sam <garming@catalyst.net.nz>
BUG: https://bugzilla.samba.org/show_bug.cgi?id=12382

Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 2dfedffb740ecfe898945a9fc47b24e3c8328d7e)

1 files changed, 216 insertions, 169 deletions

diff --git a/source4/dsdb/kcc/garbage_collect_tombstones.c b/source4/dsdb/kcc/garbage_collect_tombstones.c
index 8d2ea8b477a..62e98137adf 100644
--- a/source4/dsdb/kcc/garbage_collect_tombstones.c
+++ b/source4/dsdb/kcc/garbage_collect_tombstones.c
@@ -33,6 +33,209 @@
 #include "lib/ldb-samba/ldb_matching_rules.h"
 #include "lib/util/time.h"
 
+static NTSTATUS garbage_collect_tombstones_part(TALLOC_CTX *mem_ctx,
+						struct ldb_context *samdb,
+						struct dsdb_ldb_dn_list_node *part,
+						char *filter,
+						unsigned int *num_links_removed,
+						unsigned int *num_objects_removed,
+						struct dsdb_schema *schema,
+						const char **attrs,
+						char **error_string,
+						NTTIME expunge_time_nttime)
+{
+	int ret;
+	struct ldb_dn *do_dn;
+	struct ldb_result *res;
+	unsigned int i, j, k;
+	uint32_t flags;
+	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
+	if (!tmp_ctx) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	ret = dsdb_get_deleted_objects_dn(samdb, tmp_ctx, part->dn, &do_dn);
+	if (ret != LDB_SUCCESS) {
+		TALLOC_FREE(tmp_ctx);
+		/* some partitions have no Deleted Objects
+		   container */
+		return NT_STATUS_OK;
+	}
+
+	DEBUG(1, ("Doing a full scan on %s and looking for deleted objects\n",
+		  ldb_dn_get_linearized(part->dn)));
+
+	flags = DSDB_SEARCH_SHOW_RECYCLED |
+		DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT |
+		DSDB_SEARCH_REVEAL_INTERNALS;
+	ret = dsdb_search(samdb, tmp_ctx, &res, part->dn, LDB_SCOPE_SUBTREE,
+			  attrs, flags, "%s", filter);
+
+	if (ret != LDB_SUCCESS) {
+		*error_string = talloc_asprintf(mem_ctx,
+						"Failed to search for deleted "
+						"objects in %s: %s",
+						ldb_dn_get_linearized(do_dn),
+						ldb_errstring(samdb));
+		TALLOC_FREE(tmp_ctx);
+		return NT_STATUS_INTERNAL_ERROR;
+	}
+
+	for (i=0; i<res->count; i++) {
+		struct ldb_message *cleanup_msg = NULL;
+		unsigned int num_modified = 0;
+
+		bool isDeleted = ldb_msg_find_attr_as_bool(res->msgs[i],
+							   "isDeleted", false);
+		if (isDeleted) {
+			if (ldb_dn_compare(do_dn, res->msgs[i]->dn) == 0) {
+				/* Skip the Deleted Object Container */
+				continue;
+			}
+
+			ret = dsdb_delete(samdb, res->msgs[i]->dn,
+					  DSDB_SEARCH_SHOW_RECYCLED
+					  |DSDB_MODIFY_RELAX);
+			if (ret != LDB_SUCCESS) {
+				DEBUG(1,(__location__ ": Failed to remove "
+					 "deleted object %s\n",
+					 ldb_dn_get_linearized(res->
+							       msgs[i]->dn)));
+			} else {
+				DEBUG(4,("Removed deleted object %s\n",
+					 ldb_dn_get_linearized(res->
+							       msgs[i]->dn)));
+				(*num_objects_removed)++;
+			}
+			continue;
+		}
+
+		/* This must have a linked attribute */
+
+		/*
+		 * From MS-ADTS 3.1.1.1.9 DCs, usn Counters, and
+		 * the Originating Update Stamp
+		 *
+		 * "A link value r is deleted, but exists as a
+		 *  tombstone, if r.stamp.timeDeleted ≠ 0. When
+		 *  the current time minus r.stamp.timeDeleted
+		 *  exceeds the tombstone lifetime, the link
+		 *  value r is garbage-collected; that is,
+		 *  removed from its containing forward link
+		 *  attribute. "
+		 */
+
+		for (j=0; j < res->msgs[i]->num_elements; j++) {
+			struct ldb_message_element *element = NULL;
+			/* TODO this is O(log n) per attribute with deleted values */
+			const struct dsdb_attribute *attrib = NULL;
+
+			element = &res->msgs[i]->elements[j];
+			attrib = dsdb_attribute_by_lDAPDisplayName(schema,
+								   element->name);
+
+			/* This avoids parsing isDeleted as a link */
+			if (attrib->linkID == 0 || ((attrib->linkID & 1) == 1)) {
+				continue;
+			}
+
+			for (k = 0; k < element->num_values; k++) {
+				struct ldb_val *value = &element->values[k];
+				uint64_t whenChanged = 0;
+				NTSTATUS status;
+				struct dsdb_dn *dn;
+				struct ldb_message_element *cleanup_elem = NULL;
+				char *guid_search_str = NULL;
+				char *guid_buf_str = NULL;
+				struct ldb_val cleanup_val;
+				struct GUID_txt_buf buf_guid;
+				struct GUID guid;
+				const struct ldb_val *guid_blob;
+
+				if (dsdb_dn_is_deleted_val(value) == false) {
+					continue;
+				}
+
+				dn = dsdb_dn_parse(tmp_ctx, samdb,
+						   &element->values[k],
+						   attrib->syntax->ldap_oid);
+				if (dn == NULL) {
+					DEBUG(1, ("Failed to parse linked attribute blob of "
+						  "%s on %s while expunging expired links\n",
+						  element->name,
+						  ldb_dn_get_linearized(res->msgs[i]->dn)));
+					continue;
+				}
+
+				status = dsdb_get_extended_dn_uint64(dn->dn,
+								     &whenChanged,
+								     "RMD_CHANGETIME");
+				if (!NT_STATUS_IS_OK(status)) {
+					DEBUG(1, ("Error: RMD_CHANGETIME is missing on a forward link.\n"));
+					talloc_free(dn);
+					continue;
+				}
+
+				if (whenChanged >= expunge_time_nttime) {
+					talloc_free(dn);
+					continue;
+				}
+
+				guid_blob = ldb_dn_get_extended_component(dn->dn, "GUID");
+				status = GUID_from_ndr_blob(guid_blob, &guid);
+				if (!NT_STATUS_IS_OK(status)) {
+					DEBUG(1, ("Error: Invalid GUID on link target.\n"));
+					talloc_free(dn);
+					continue;
+				}
+
+				guid_buf_str = GUID_buf_string(&guid, &buf_guid);
+				guid_search_str = talloc_asprintf(mem_ctx,
+								  "<GUID=%s>",
+								  guid_buf_str);
+				cleanup_val = data_blob_string_const(guid_search_str);
+
+				talloc_free(dn);
+
+				if (cleanup_msg == NULL) {
+					cleanup_msg = ldb_msg_new(mem_ctx);
+					if (cleanup_msg == NULL) {
+						return NT_STATUS_NO_MEMORY;
+					}
+					cleanup_msg->dn = res->msgs[i]->dn;
+				}
+
+				ret = ldb_msg_add_value(cleanup_msg,
+							element->name,
+							&cleanup_val,
+							&cleanup_elem);
+				if (ret != LDB_SUCCESS) {
+					return NT_STATUS_NO_MEMORY;
+				}
+				cleanup_elem->flags = LDB_FLAG_MOD_DELETE;
+				num_modified++;
+			}
+		}
+
+		if (num_modified > 0) {
+			ret = dsdb_modify(samdb, cleanup_msg,
+					  DSDB_REPLMD_VANISH_LINKS);
+			if (ret != LDB_SUCCESS) {
+				DEBUG(1,(__location__ ": Failed to remove deleted object %s\n",
+					 ldb_dn_get_linearized(res->msgs[i]->dn)));
+			} else {
+				DEBUG(4,("Removed deleted object %s\n",
+					 ldb_dn_get_linearized(res->msgs[i]->dn)));
+				*num_links_removed = *num_links_removed + num_modified;
+			}
+
+		}
+	}
+
+	TALLOC_FREE(tmp_ctx);
+	return NT_STATUS_OK;
+}
+
 /*
  * Per MS-ADTS 3.1.1.5.5 Delete Operation
  *
@@ -58,11 +261,9 @@ NTSTATUS dsdb_garbage_collect_tombstones(TALLOC_CTX *mem_ctx,
 					 unsigned int *num_links_removed,
 					 char **error_string)
 {
-	int ret;
-
 	const char **attrs = NULL;
 	char *filter = NULL;
-
+	NTSTATUS status;
 	unsigned int i;
 	struct dsdb_attribute *next_attr;
 	unsigned int num_link_attrs;
@@ -117,178 +318,24 @@ NTSTATUS dsdb_garbage_collect_tombstones(TALLOC_CTX *mem_ctx,
 	attrs[i] = "isDeleted";
 	attrs[i+1] = NULL;
 
-	filter = talloc_asprintf_append(filter, "(&(isDeleted=TRUE)(whenChanged<=%s)))", expunge_time_string);
+	filter = talloc_asprintf_append(filter,
+					"(&(isDeleted=TRUE)(whenChanged<=%s)))",
+					expunge_time_string);
 	if (filter == NULL) {
 		return NT_STATUS_NO_MEMORY;
 	}
 
-	schema = dsdb_get_schema(samdb, mem_ctx);
-
 	for (; part != NULL; part = part->next) {
-		struct ldb_dn *do_dn;
-		struct ldb_result *res;
-		unsigned int j, k;
-		uint32_t flags;
-		TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
-		if (!tmp_ctx) {
-			return NT_STATUS_NO_MEMORY;
-		}
-
-		ret = dsdb_get_deleted_objects_dn(samdb, tmp_ctx, part->dn, &do_dn);
-		if (ret != LDB_SUCCESS) {
-			TALLOC_FREE(tmp_ctx);
-			/* some partitions have no Deleted Objects
-			   container */
-			continue;
-		}
-
-		DEBUG(1, ("Doing a full scan on %s and looking for deleted objects\n",
-			  ldb_dn_get_linearized(part->dn)));
-
-		flags = DSDB_SEARCH_SHOW_RECYCLED |
-			DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT |
-			DSDB_SEARCH_REVEAL_INTERNALS;
-		ret = dsdb_search(samdb, tmp_ctx, &res, part->dn, LDB_SCOPE_SUBTREE,
-				  attrs, flags, "%s", filter);
-
-		if (ret != LDB_SUCCESS) {
-			*error_string = talloc_asprintf(mem_ctx, "Failed to search for deleted objects in %s: %s",
-							ldb_dn_get_linearized(do_dn),
-							ldb_errstring(samdb));
-			TALLOC_FREE(tmp_ctx);
-			return NT_STATUS_INTERNAL_ERROR;
+		status = garbage_collect_tombstones_part(mem_ctx, samdb, part,
+							 filter,
+							 num_links_removed,
+							 num_objects_removed,
+							 schema, attrs,
+							 error_string,
+							 expunge_time_nttime);
+		if (!NT_STATUS_IS_OK(status)) {
+			return status;
 		}
-
-		for (i=0; i<res->count; i++) {
-			struct ldb_message *cleanup_msg = NULL;
-			unsigned int num_modified = 0;
-
-			bool isDeleted = ldb_msg_find_attr_as_bool(res->msgs[i], "isDeleted", false);
-			if (isDeleted) {
-				if (ldb_dn_compare(do_dn, res->msgs[i]->dn) == 0) {
-					/* Skip the Deleted Object Container */
-					continue;
-				}
-
-				ret = dsdb_delete(samdb, res->msgs[i]->dn, DSDB_SEARCH_SHOW_RECYCLED|DSDB_MODIFY_RELAX);
-				if (ret != LDB_SUCCESS) {
-					DEBUG(1,(__location__ ": Failed to remove deleted object %s\n",
-						 ldb_dn_get_linearized(res->msgs[i]->dn)));
-				} else {
-					DEBUG(4,("Removed deleted object %s\n",
-						 ldb_dn_get_linearized(res->msgs[i]->dn)));
-					(*num_objects_removed)++;
-				}
-				continue;
-			}
-
-			/* This must have a linked attribute */
-
-			/*
-			 * From MS-ADTS 3.1.1.1.9 DCs, usn Counters, and the Originating Update Stamp
-			 *
-			 * "A link value r is deleted, but exists as a
-			 *  tombstone, if r.stamp.timeDeleted ≠ 0. When
-			 *  the current time minus r.stamp.timeDeleted
-			 *  exceeds the tombstone lifetime, the link
-			 *  value r is garbage-collected; that is,
-			 *  removed from its containing forward link
-			 *  attribute. "
-			 */
-
-			for (j=0; j < res->msgs[i]->num_elements; j++) {
-				struct ldb_message_element *element = &res->msgs[i]->elements[j];
-				/* TODO this is O(log n) per attribute with deleted values */
-				const struct dsdb_attribute *attrib
-					= dsdb_attribute_by_lDAPDisplayName(schema, element->name);
-
-				/* This avoids parsing isDeleted as a link */
-				if (attrib->linkID == 0 || ((attrib->linkID & 1) == 1)) {
-					continue;
-				}
-
-				for (k = 0; k < element->num_values; k++) {
-					struct ldb_val *value = &element->values[k];
-					uint64_t whenChanged = 0;
-					NTSTATUS status;
-					struct dsdb_dn *dn;
-					struct ldb_message_element *cleanup_elem = NULL;
-					char *guid_search_str = NULL, *guid_buf_str = NULL;
-					struct ldb_val cleanup_val;
-					struct GUID_txt_buf buf_guid;
-					struct GUID guid;
-					const struct ldb_val *guid_blob;
-
-					if (dsdb_dn_is_deleted_val(value) == false) {
-						continue;
-					}
-
-					dn = dsdb_dn_parse(tmp_ctx, samdb, &element->values[k],
-							   attrib->syntax->ldap_oid);
-					if (dn == NULL) {
-						DEBUG(1, ("Failed to parse linked attribute blob of %s on %s while expunging expired links\n", element->name,
-							  ldb_dn_get_linearized(res->msgs[i]->dn)));
-						continue;
-					}
-
-					status = dsdb_get_extended_dn_uint64(dn->dn, &whenChanged, "RMD_CHANGETIME");
-					if (!NT_STATUS_IS_OK(status)) {
-						DEBUG(1, ("Error: RMD_CHANGETIME is missing on a forward link.\n"));
-						talloc_free(dn);
-						continue;
-					}
-
-					if (whenChanged >= expunge_time_nttime) {
-						talloc_free(dn);
-						continue;
-					}
-
-					guid_blob = ldb_dn_get_extended_component(dn->dn, "GUID");
-					status = GUID_from_ndr_blob(guid_blob, &guid);
-					if (!NT_STATUS_IS_OK(status)) {
-						DEBUG(1, ("Error: Invalid GUID on link target.\n"));
-						talloc_free(dn);
-						continue;
-					}
-
-					guid_buf_str = GUID_buf_string(&guid, &buf_guid);
-					guid_search_str = talloc_asprintf(mem_ctx, "<GUID=%s>", guid_buf_str);
-					cleanup_val = data_blob_string_const(guid_search_str);
-
-					talloc_free(dn);
-
-					if (cleanup_msg == NULL) {
-						cleanup_msg = ldb_msg_new(mem_ctx);
-						if (cleanup_msg == NULL) {
-							return NT_STATUS_NO_MEMORY;
-						}
-						cleanup_msg->dn = res->msgs[i]->dn;
-					}
-
-					ret = ldb_msg_add_value(cleanup_msg, element->name, &cleanup_val, &cleanup_elem);
-					if (ret != LDB_SUCCESS) {
-						return NT_STATUS_NO_MEMORY;
-					}
-					cleanup_elem->flags = LDB_FLAG_MOD_DELETE;
-					num_modified++;
-				}
-			}
-
-			if (num_modified > 0) {
-				ret = dsdb_modify(samdb, cleanup_msg, DSDB_REPLMD_VANISH_LINKS);
-				if (ret != LDB_SUCCESS) {
-					DEBUG(1,(__location__ ": Failed to remove deleted object %s\n",
-						 ldb_dn_get_linearized(res->msgs[i]->dn)));
-				} else {
-					DEBUG(4,("Removed deleted object %s\n",
-						 ldb_dn_get_linearized(res->msgs[i]->dn)));
-					*num_links_removed = *num_links_removed + num_modified;
-				}
-
-			}
-		}
-		TALLOC_FREE(tmp_ctx);
-
 	}
 
 	return NT_STATUS_OK;