From 4ff20fcd31bef1df561e6ae513581202b259c1f0 Mon Sep 17 00:00:00 2001 From: Andrew Bartlett Date: Fri, 30 Dec 2005 08:50:47 +0000 Subject: r12600: Add a new module to sort the objectclass attribute on store. The module is perhaps not the most efficient, but I think it is reasonable. This should restore operation of MMC against Samba4 (broken by the templating fixes). Andrew Bartlett (This used to be commit 41948c4bdbfca1160a01a92994324f9e22422afe) --- source4/lib/ldb/common/ldb_modules.c | 1 + source4/lib/ldb/config.mk | 9 + source4/lib/ldb/include/dlinklist.h | 4 +- source4/lib/ldb/modules/objectclass.c | 313 ++++++++++++++++++++++++++++++++++ source4/setup/provision_init.ldif | 2 +- 5 files changed, 327 insertions(+), 2 deletions(-) create mode 100644 source4/lib/ldb/modules/objectclass.c diff --git a/source4/lib/ldb/common/ldb_modules.c b/source4/lib/ldb/common/ldb_modules.c index 8076dbfdf9..5c2e36d431 100644 --- a/source4/lib/ldb/common/ldb_modules.c +++ b/source4/lib/ldb/common/ldb_modules.c @@ -130,6 +130,7 @@ int ldb_load_modules(struct ldb_context *ldb, const char *options[]) { "schema", schema_module_init }, { "operational", operational_module_init }, { "rdn_name", rdn_name_module_init }, + { "objectclass", objectclass_module_init }, #ifdef _SAMBA_BUILD_ { "objectguid", objectguid_module_init }, { "samldb", samldb_module_init }, diff --git a/source4/lib/ldb/config.mk b/source4/lib/ldb/config.mk index 2ce0d5043d..9cb74f551b 100644 --- a/source4/lib/ldb/config.mk +++ b/source4/lib/ldb/config.mk @@ -7,6 +7,15 @@ OBJ_FILES = \ # End MODULE libldb_operational ################################################ +################################################ +# Start MODULE libldb_objectclass +[MODULE::libldb_objectclass] +SUBSYSTEM = LIBLDB +OBJ_FILES = \ + modules/objectclass.o +# End MODULE libldb_objectclass +################################################ + ################################################ # Start MODULE libldb_rdn_name [MODULE::libldb_rdn_name] diff --git a/source4/lib/ldb/include/dlinklist.h b/source4/lib/ldb/include/dlinklist.h index 40f7f0a0c7..a39007375f 100644 --- a/source4/lib/ldb/include/dlinklist.h +++ b/source4/lib/ldb/include/dlinklist.h @@ -88,6 +88,8 @@ do { \ type tmp; \ for (tmp = (list1); tmp->next; tmp = tmp->next) ; \ tmp->next = (list2); \ - (list2)->prev = tmp; \ + if (list2) { \ + (list2)->prev = tmp; \ + } \ } \ } while (0) diff --git a/source4/lib/ldb/modules/objectclass.c b/source4/lib/ldb/modules/objectclass.c new file mode 100644 index 0000000000..b89b70ebf2 --- /dev/null +++ b/source4/lib/ldb/modules/objectclass.c @@ -0,0 +1,313 @@ +/* + ldb database library + + Copyright (C) Andrew Bartlett 2005 + + ** NOTE! The following LGPL license applies to the ldb + ** library. This does NOT imply that all of Samba is released + ** under the LGPL + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ + +/* + * Name: ldb + * + * Component: objectClass sorting module + * + * Description: sort the objectClass attribute into the class hierarchy + * + * Author: Andrew Bartlett + */ + +#include "includes.h" +#include "ldb/include/ldb.h" +#include "ldb/include/ldb_private.h" +#include "ldb/include/ldb_errors.h" +#include "ldb/include/dlinklist.h" + +/* It turns out the MMC assumes that the last objectClass in the list + * is the most specific subclass. As such, we must sort the list, + * according to the schema. + * + * For performance, we do this on the add/modify, not on the search + * + * We perform the original add/modify, then search for that is now in + * the objectClass list. We can then then replace that with the new + * sorted list. The backend is expected to preserve ordering for + * subsequent searches. + * + * We are in a transaction, so this is all perfectly safe... + */ + +static int objectclass_handle(struct ldb_module *module, struct ldb_request *req, const struct ldb_message *msg) +{ + TALLOC_CTX *mem_ctx; + int ret; + struct ldb_request search_request; + struct ldb_request modify_request; + struct ldb_message *modify_msg; + struct ldb_result *res; + const char *attrs[] = { "objectClass", NULL }; + struct class_list { + struct class_list *prev, *next; + const char *objectclass; + }; + struct class_list *sorted = NULL, *parent_class = NULL, + *subclass = NULL, *unsorted = NULL, *current, *poss_subclass; + int i; + int layer; + + struct ldb_message_element *objectclass_element; + + ldb_debug(module->ldb, LDB_DEBUG_TRACE, "objectclass_handle\n"); + + if (ldb_dn_is_special(msg->dn)) { /* do not manipulate our control entries */ + return ldb_next_request(module, req); + } + + ret = ldb_next_request(module, req); + + if (ret) { + return ret; + } + + if (ldb_msg_find_element(msg, "objectClass") == NULL ) { + /* No sign of the objectClass: no change, nothing to see here */ + return ret; + } + + /* Thanks to transactions: Now do a search, find the full list + * of objectClasses and do the sort */ + + search_request.operation = LDB_REQ_SEARCH; + search_request.op.search.base = msg->dn; + search_request.op.search.scope = LDB_SCOPE_BASE; + search_request.op.search.tree = ldb_parse_tree(module->ldb, NULL); + search_request.op.search.attrs = attrs; + + ret = ldb_next_request(module, &search_request); + if (ret) { + return ret; + } + + mem_ctx = talloc_new(module); + if (!mem_ctx) { + return LDB_ERR_OPERATIONS_ERROR; + } + + res = search_request.op.search.res; + talloc_steal(mem_ctx, res); + if (res->count != 1) { + ldb_set_errstring(module, + talloc_asprintf(mem_ctx, "objectClass_handle: " + "search for %s found %d != 1 objects, for entry we just added/modified", + ldb_dn_linearize(mem_ctx, msg->dn), + res->count)); + /* What happened? The above add/modify worked... */ + talloc_free(mem_ctx); + return LDB_ERR_NO_SUCH_OBJECT; + } + + /* This is now the objectClass list from the database */ + objectclass_element = ldb_msg_find_element(res->msgs[0], "objectClass"); + if (!objectclass_element) { + /* Perhaps the above was a remove? Move along now, nothing to see here */ + talloc_free(mem_ctx); + return LDB_SUCCESS; + } + + /* DESIGN: + * + * We work on 4 different 'bins' (implemented here as linked lists): + * + * * sorted: the eventual list, in the order we wish to push + * into the database. This is the only ordered list. + * + * * parent_class: The current parent class 'bin' we are + * trying to find subclasses for + * + * * subclass: The subclasses we have found so far + * + * * unsorted: The remaining objectClasses + * + * The process is a matter of filtering objectClasses up from + * unsorted into sorted. Order is irrelevent in the later 3 'bins'. + * + * We start with 'top' (found and promoted to parent_class + * initially). Then we find (in unsorted) all the direct + * subclasses of 'top'. parent_classes is concatenated onto + * the end of 'sorted', and subclass becomes the list in + * parent_class. + * + * We then repeat, until we find no more subclasses. Any left + * over classes are added to the end. + * + */ + + /* Firstly, dump all the objectClass elements into the + * unsorted bin, except for 'top', which is special */ + for (i=0; i < objectclass_element->num_values; i++) { + current = talloc(mem_ctx, struct class_list); + if (!current) { + talloc_free(mem_ctx); + return LDB_ERR_OPERATIONS_ERROR; + } + current->objectclass = (const char *)objectclass_element->values[i].data; + + /* this is the root of the tree. We will start + * looking for subclasses from here */ + if (ldb_attr_cmp("top", current->objectclass) == 0) { + DLIST_ADD(parent_class, current); + } else { + DLIST_ADD(unsorted, current); + } + } + + /* DEBUGGING aid: how many layers are we down now? */ + layer = 0; + do { + layer++; + /* Find all the subclasses of classes in the + * parent_classes. Push them onto the subclass list */ + + /* Ensure we don't bother if there are no unsorted entries left */ + for (current = parent_class; unsorted && current; current = current->next) { + const char **subclasses = ldb_subclass_list(module->ldb, current->objectclass); + + /* Walk the list of possible subclasses in unsorted */ + for (poss_subclass = unsorted; poss_subclass; ) { + struct class_list *next; + + /* Save the next pointer, as the DLIST_ macros will change poss_subclass->next */ + next = poss_subclass->next; + + for (i = 0; subclasses && subclasses[i]; i++) { + if (ldb_attr_cmp(poss_subclass->objectclass, subclasses[i]) == 0) { + DLIST_REMOVE(unsorted, poss_subclass); + DLIST_ADD(subclass, poss_subclass); + + break; + } + } + poss_subclass = next; + } + } + + /* Now push the parent_classes as sorted, we are done with + these. Add to the END of the list by concatenation */ + DLIST_CONCATENATE(sorted, parent_class, struct class_list *); + + /* and now find subclasses of these */ + parent_class = subclass; + subclass = NULL; + + /* If we didn't find any subclasses we will fall out + * the bottom here */ + } while (parent_class); + + /* This shouldn't happen, and would break MMC, but we can't + * afford to loose objectClasses. Perhaps there was no 'top', + * or some other schema error? + * + * Detecting schema errors is the job of the schema module, so + * at this layer we just try not to loose data + */ + DLIST_CONCATENATE(sorted, unsorted, struct class_list *); + + modify_msg = ldb_msg_new(mem_ctx); + if (!modify_msg) { + talloc_free(mem_ctx); + return LDB_ERR_OPERATIONS_ERROR; + } + modify_msg->dn = talloc_reference(modify_msg, msg->dn); + + /* We must completely replace the existing objectClass entry. + * We could do a constrained add/del, but we are meant to be + * in a transaction... */ + + ret = ldb_msg_add_empty(modify_msg, "objectClass", LDB_FLAG_MOD_REPLACE); + if (ret != LDB_SUCCESS) { + talloc_free(mem_ctx); + return ret; + } + + /* Move from the linked list back into an ldb msg */ + for (current = sorted; current; current = current->next) { + ret = ldb_msg_add_string(modify_msg, "objectClass", current->objectclass); + if (ret != LDB_SUCCESS) { + talloc_free(mem_ctx); + return ret; + } + } + + ret = ldb_msg_sanity_check(modify_msg); + if (ret != LDB_SUCCESS) { + talloc_free(mem_ctx); + return ret; + } + + modify_request.operation = LDB_REQ_MODIFY; + modify_request.op.mod.message = modify_msg; + + /* And now push the write into the database */ + ret = ldb_next_request(module, &modify_request); + + talloc_free(mem_ctx); + return ret; +} + +static int objectclass_request(struct ldb_module *module, struct ldb_request *req) +{ + switch (req->operation) { + + /* only care about add and modify requests */ + case LDB_REQ_ADD: + return objectclass_handle(module, req, req->op.add.message); + + case LDB_REQ_MODIFY: + return objectclass_handle(module, req, req->op.mod.message); + + default: + return ldb_next_request(module, req); + + } +} + +static const struct ldb_module_ops objectclass_ops = { + .name = "objectclass", + .request = objectclass_request, +}; + +#ifdef HAVE_DLOPEN_DISABLED +struct ldb_module *init_module(struct ldb_context *ldb, const char *options[]) +#else +struct ldb_module *objectclass_module_init(struct ldb_context *ldb, const char *options[]) +#endif +{ + struct ldb_module *ctx; + + ctx = talloc(ldb, struct ldb_module); + if (!ctx) + return NULL; + + ctx->private_data = NULL; + + ctx->ldb = ldb; + ctx->prev = ctx->next = NULL; + ctx->ops = &objectclass_ops; + + return ctx; +} diff --git a/source4/setup/provision_init.ldif b/source4/setup/provision_init.ldif index e4c2476992..ff6b1def19 100644 --- a/source4/setup/provision_init.ldif +++ b/source4/setup/provision_init.ldif @@ -70,5 +70,5 @@ isSynchronized: TRUE #Add modules to the list to activate them by default #beware often order is important dn: @MODULES -@LIST: rootdse,samldb,password_hash,operational,objectguid,rdn_name +@LIST: rootdse,samldb,password_hash,operational,objectguid,rdn_name,objectclass -- cgit