From 3b056061ff7f11e70532b859320638f9c8f5f2c7 Mon Sep 17 00:00:00 2001 From: Andrew Tridgell Date: Wed, 16 Dec 2009 11:34:33 +1100 Subject: s4-dsdb: added support for backlinks in repl_meta_data backlinks need more careful handling now that we store the additional meta data for deleted links. It is easier to handle this in repl_meta_data than in linked_attributes. Eventually linked_attributes will disappear, with the functionality moved into repl_meta_data. Pair-Programmed-With: Andrew Bartlett --- source4/dsdb/samdb/ldb_modules/repl_meta_data.c | 244 ++++++++++++++++++++++-- 1 file changed, 224 insertions(+), 20 deletions(-) (limited to 'source4/dsdb/samdb/ldb_modules/repl_meta_data.c') diff --git a/source4/dsdb/samdb/ldb_modules/repl_meta_data.c b/source4/dsdb/samdb/ldb_modules/repl_meta_data.c index 249dd61a4a..7488a1bee9 100644 --- a/source4/dsdb/samdb/ldb_modules/repl_meta_data.c +++ b/source4/dsdb/samdb/ldb_modules/repl_meta_data.c @@ -53,6 +53,8 @@ struct replmd_private { TALLOC_CTX *la_ctx; struct la_entry *la_list; + TALLOC_CTX *bl_ctx; + struct la_backlink *la_backlinks; struct nc_entry { struct nc_entry *prev, *next; struct ldb_dn *dn; @@ -87,6 +89,7 @@ struct replmd_replicated_request { static int replmd_replicated_apply_next(struct replmd_replicated_request *ar); + /* initialise the module allocate the private structure and build the list @@ -107,6 +110,169 @@ static int replmd_init(struct ldb_module *module) return ldb_next_init(module); } +/* + cleanup our per-transaction contexts + */ +static void replmd_txn_cleanup(struct replmd_private *replmd_private) +{ + talloc_free(replmd_private->la_ctx); + replmd_private->la_list = NULL; + replmd_private->la_ctx = NULL; + + talloc_free(replmd_private->bl_ctx); + replmd_private->la_backlinks = NULL; + replmd_private->bl_ctx = NULL; +} + + +struct la_backlink { + struct la_backlink *next, *prev; + const char *attr_name; + struct GUID forward_guid, target_guid; + bool active; +}; + +/* + add a backlink to the list of backlinks to add/delete in the prepare + commit + */ +static int replmd_add_backlink(struct ldb_module *module, const struct dsdb_schema *schema, + struct GUID *forward_guid, struct GUID *target_guid, + bool active, const struct dsdb_attribute *schema_attr) +{ + const struct dsdb_attribute *target_attr; + struct la_backlink *bl; + struct replmd_private *replmd_private = + talloc_get_type_abort(ldb_module_get_private(module), struct replmd_private); + + target_attr = dsdb_attribute_by_linkID(schema, schema_attr->linkID + 1); + if (!target_attr) { + /* + * windows 2003 has a broken schema where the + * definition of msDS-IsDomainFor is missing (which is + * supposed to be the backlink of the + * msDS-HasDomainNCs attribute + */ + return LDB_SUCCESS; + } + + /* see if its already in the list */ + for (bl=replmd_private->la_backlinks; bl; bl=bl->next) { + if (GUID_equal(forward_guid, &bl->forward_guid) && + GUID_equal(target_guid, &bl->target_guid) && + (target_attr->lDAPDisplayName == bl->attr_name || + strcmp(target_attr->lDAPDisplayName, bl->attr_name) == 0)) { + break; + } + } + + if (bl) { + /* we found an existing one */ + if (bl->active == active) { + return LDB_SUCCESS; + } + DLIST_REMOVE(replmd_private->la_backlinks, bl); + talloc_free(bl); + return LDB_SUCCESS; + } + + if (replmd_private->bl_ctx == NULL) { + replmd_private->bl_ctx = talloc_new(replmd_private); + if (replmd_private->bl_ctx == NULL) { + ldb_module_oom(module); + return LDB_ERR_OPERATIONS_ERROR; + } + } + + /* its a new one */ + bl = talloc(replmd_private->bl_ctx, struct la_backlink); + if (bl == NULL) { + ldb_module_oom(module); + return LDB_ERR_OPERATIONS_ERROR; + } + + bl->attr_name = target_attr->lDAPDisplayName; + bl->forward_guid = *forward_guid; + bl->target_guid = *target_guid; + bl->active = active; + + DLIST_ADD(replmd_private->la_backlinks, bl); + + return LDB_SUCCESS; +} + +/* + process the list of backlinks we accumulated during + a transaction, adding and deleting the backlinks + from the target objects + */ +static int replmd_process_backlink(struct ldb_module *module, struct la_backlink *bl) +{ + struct ldb_dn *target_dn, *source_dn; + int ret; + struct ldb_context *ldb = ldb_module_get_ctx(module); + struct ldb_message *msg; + TALLOC_CTX *tmp_ctx = talloc_new(bl); + char *dn_string; + + /* + - find DN of target + - find DN of source + - construct ldb_message + - either an add or a delete + */ + ret = dsdb_module_dn_by_guid(module, tmp_ctx, &bl->target_guid, &target_dn); + if (ret != LDB_SUCCESS) { + ldb_asprintf_errstring(ldb, "Failed to find target DN for linked attribute with GUID %s\n", + GUID_string(bl, &bl->target_guid)); + talloc_free(tmp_ctx); + return ret; + } + + ret = dsdb_module_dn_by_guid(module, tmp_ctx, &bl->forward_guid, &source_dn); + if (ret != LDB_SUCCESS) { + ldb_asprintf_errstring(ldb, "Failed to find source DN for linked attribute with GUID %s\n", + GUID_string(bl, &bl->forward_guid)); + talloc_free(tmp_ctx); + return ret; + } + + msg = ldb_msg_new(tmp_ctx); + if (msg == NULL) { + ldb_module_oom(module); + talloc_free(tmp_ctx); + return LDB_ERR_OPERATIONS_ERROR; + } + + /* construct a ldb_message for adding/deleting the backlink */ + msg->dn = target_dn; + dn_string = ldb_dn_get_extended_linearized(tmp_ctx, source_dn, 1); + if (!dn_string) { + ldb_module_oom(module); + talloc_free(tmp_ctx); + return LDB_ERR_OPERATIONS_ERROR; + } + ret = ldb_msg_add_steal_string(msg, bl->attr_name, dn_string); + if (ret != LDB_SUCCESS) { + talloc_free(tmp_ctx); + return ret; + } + msg->elements[0].flags = bl->active?LDB_FLAG_MOD_ADD:LDB_FLAG_MOD_DELETE; + + ret = dsdb_module_modify(module, msg, 0); + if (ret != LDB_SUCCESS) { + ldb_asprintf_errstring(ldb, "Failed to %s backlink from %s to %s - %s", + bl->active?"add":"remove", + ldb_dn_get_linearized(source_dn), + ldb_dn_get_linearized(target_dn), + ldb_errstring(ldb)); + talloc_free(tmp_ctx); + return ret; + } + talloc_free(tmp_ctx); + return ret; +} + /* * Callback for most write operations in this module: @@ -1097,12 +1263,14 @@ static int replmd_update_la_val(TALLOC_CTX *mem_ctx, struct ldb_val *v, struct p handle adding a linked attribute */ static int replmd_modify_la_add(struct ldb_module *module, + struct dsdb_schema *schema, struct ldb_message *msg, struct ldb_message_element *el, struct ldb_message_element *old_el, const struct dsdb_attribute *schema_attr, uint64_t seq_num, - time_t t) + time_t t, + struct GUID *msg_guid) { int i; struct parsed_dn *dns, *old_dns; @@ -1166,6 +1334,12 @@ static int replmd_modify_la_add(struct ldb_module *module, return ret; } } + + ret = replmd_add_backlink(module, schema, msg_guid, dns[i].guid, true, schema_attr); + if (ret != LDB_SUCCESS) { + talloc_free(tmp_ctx); + return ret; + } } /* add the new ones on to the end of the old values, constructing a new el->values */ @@ -1197,12 +1371,14 @@ static int replmd_modify_la_add(struct ldb_module *module, handle deleting all active linked attributes */ static int replmd_modify_la_delete(struct ldb_module *module, + struct dsdb_schema *schema, struct ldb_message *msg, struct ldb_message_element *el, struct ldb_message_element *old_el, const struct dsdb_attribute *schema_attr, uint64_t seq_num, - time_t t) + time_t t, + struct GUID *msg_guid) { int i; struct parsed_dn *dns, *old_dns; @@ -1280,6 +1456,12 @@ static int replmd_modify_la_delete(struct ldb_module *module, talloc_free(tmp_ctx); return ret; } + + ret = replmd_add_backlink(module, schema, msg_guid, old_dns[i].guid, false, schema_attr); + if (ret != LDB_SUCCESS) { + talloc_free(tmp_ctx); + return ret; + } } el->values = talloc_steal(msg->elements, old_el->values); @@ -1298,12 +1480,14 @@ static int replmd_modify_la_delete(struct ldb_module *module, handle replacing a linked attribute */ static int replmd_modify_la_replace(struct ldb_module *module, + struct dsdb_schema *schema, struct ldb_message *msg, struct ldb_message_element *el, struct ldb_message_element *old_el, const struct dsdb_attribute *schema_attr, uint64_t seq_num, - time_t t) + time_t t, + struct GUID *msg_guid) { int i; struct parsed_dn *dns, *old_dns; @@ -1344,13 +1528,20 @@ static int replmd_modify_la_replace(struct ldb_module *module, struct parsed_dn *p; const struct ldb_val *v; + v = ldb_dn_get_extended_component(old_p->dsdb_dn->dn, "DELETED"); + if (v) continue; + + ret = replmd_add_backlink(module, schema, msg_guid, old_dns[i].guid, false, schema_attr); + if (ret != LDB_SUCCESS) { + talloc_free(tmp_ctx); + return ret; + } + p = parsed_dn_find(dns, el->num_values, old_p->guid); if (p) { /* we don't delete it if we are re-adding it */ continue; } - v = ldb_dn_get_extended_component(old_p->dsdb_dn->dn, "DELETED"); - if (v) continue; ret = replmd_update_la_val(old_el->values, old_p->v, old_p, old_p, invocation_id, seq_num, t, true); @@ -1394,6 +1585,12 @@ static int replmd_modify_la_replace(struct ldb_module *module, } num_new_values++; } + + ret = replmd_add_backlink(module, schema, msg_guid, dns[i].guid, true, schema_attr); + if (ret != LDB_SUCCESS) { + talloc_free(tmp_ctx); + return ret; + } } /* add the new values to the end of old_el */ @@ -1436,6 +1633,7 @@ static int replmd_modify_handle_linked_attribs(struct ldb_module *module, struct ldb_context *ldb = ldb_module_get_ctx(module); struct ldb_message *old_msg; struct dsdb_schema *schema = dsdb_get_schema(ldb); + struct GUID old_guid; if (seq_num == 0) { /* there the replmd_update_rpmd code has already @@ -1462,6 +1660,8 @@ static int replmd_modify_handle_linked_attribs(struct ldb_module *module, } old_msg = res->msgs[0]; + old_guid = samdb_result_guid(old_msg, "objectGUID"); + for (i=0; inum_elements; i++) { struct ldb_message_element *el = &msg->elements[i]; struct ldb_message_element *old_el, *new_el; @@ -1484,13 +1684,13 @@ static int replmd_modify_handle_linked_attribs(struct ldb_module *module, old_el = ldb_msg_find_element(old_msg, el->name); switch (el->flags & LDB_FLAG_MOD_MASK) { case LDB_FLAG_MOD_REPLACE: - ret = replmd_modify_la_replace(module, msg, el, old_el, schema_attr, seq_num, t); + ret = replmd_modify_la_replace(module, schema, msg, el, old_el, schema_attr, seq_num, t, &old_guid); break; case LDB_FLAG_MOD_DELETE: - ret = replmd_modify_la_delete(module, msg, el, old_el, schema_attr, seq_num, t); + ret = replmd_modify_la_delete(module, schema, msg, el, old_el, schema_attr, seq_num, t, &old_guid); break; case LDB_FLAG_MOD_ADD: - ret = replmd_modify_la_add(module, msg, el, old_el, schema_attr, seq_num, t); + ret = replmd_modify_la_add(module, schema, msg, el, old_el, schema_attr, seq_num, t, &old_guid); break; default: ldb_asprintf_errstring(ldb, @@ -2877,9 +3077,7 @@ static int replmd_start_transaction(struct ldb_module *module) /* create our private structure for this transaction */ struct replmd_private *replmd_private = talloc_get_type(ldb_module_get_private(module), struct replmd_private); - talloc_free(replmd_private->la_ctx); - replmd_private->la_list = NULL; - replmd_private->la_ctx = NULL; + replmd_txn_cleanup(replmd_private); /* free any leftover mod_usn records from cancelled transactions */ @@ -2901,6 +3099,7 @@ static int replmd_prepare_commit(struct ldb_module *module) struct replmd_private *replmd_private = talloc_get_type(ldb_module_get_private(module), struct replmd_private); struct la_entry *la, *prev; + struct la_backlink *bl; int ret; /* walk the list backwards, to do the first entry first, as we @@ -2913,16 +3112,22 @@ static int replmd_prepare_commit(struct ldb_module *module) DLIST_REMOVE(replmd_private->la_list, la); ret = replmd_process_linked_attribute(module, la); if (ret != LDB_SUCCESS) { - talloc_free(replmd_private->la_ctx); - replmd_private->la_list = NULL; - replmd_private->la_ctx = NULL; + replmd_txn_cleanup(replmd_private); return ret; } } - talloc_free(replmd_private->la_ctx); - replmd_private->la_list = NULL; - replmd_private->la_ctx = NULL; + /* process our backlink list, creating and deleting backlinks + as necessary */ + for (bl=replmd_private->la_backlinks; bl; bl=bl->next) { + ret = replmd_process_backlink(module, bl); + if (ret != LDB_SUCCESS) { + replmd_txn_cleanup(replmd_private); + return ret; + } + } + + replmd_txn_cleanup(replmd_private); /* possibly change @REPLCHANGED */ ret = replmd_notify_store(module); @@ -2937,9 +3142,8 @@ static int replmd_del_transaction(struct ldb_module *module) { struct replmd_private *replmd_private = talloc_get_type(ldb_module_get_private(module), struct replmd_private); - talloc_free(replmd_private->la_ctx); - replmd_private->la_list = NULL; - replmd_private->la_ctx = NULL; + replmd_txn_cleanup(replmd_private); + return ldb_next_del_trans(module); } -- cgit