s4:repl_meta_data: increment the attribute version with each change
[ira/wip.git] / source4 / dsdb / samdb / ldb_modules / repl_meta_data.c
index fbaf461a3fa11d0da109c52e1a687b88324c0374..1242d1d0a361412e651fa9e452931b251f9d95d6 100644 (file)
@@ -1,27 +1,23 @@
 /* 
    ldb database library
 
-   Copyright (C) Simo Sorce  2004-2006
+   Copyright (C) Simo Sorce  2004-2008
    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
    Copyright (C) Andrew Tridgell 2005
    Copyright (C) Stefan Metzmacher <metze@samba.org> 2007
 
-     ** NOTE! The following LGPL license applies to the ldb
-     ** library. This does NOT imply that all of Samba is released
-     ** under the LGPL
+   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 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 3 of the License, or (at your option) any later version.
-
-   This library is distributed in the hope that it will be useful,
+   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
-   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, see <http://www.gnu.org/licenses/>.
+   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 "lib/ldb/include/ldb.h"
-#include "lib/ldb/include/ldb_errors.h"
-#include "lib/ldb/include/ldb_private.h"
+#include "ldb_module.h"
 #include "dsdb/samdb/samdb.h"
-#include "dsdb/common/flags.h"
+#include "dsdb/common/proto.h"
+#include "../libds/common/flags.h"
 #include "librpc/gen_ndr/ndr_misc.h"
 #include "librpc/gen_ndr/ndr_drsuapi.h"
 #include "librpc/gen_ndr/ndr_drsblobs.h"
 #include "param/param.h"
+#include "libcli/security/dom_sid.h"
+#include "lib/util/dlinklist.h"
+
+struct replmd_private {
+       struct la_entry *la_list;
+};
+
+struct la_entry {
+       struct la_entry *next, *prev;
+       struct drsuapi_DsReplicaLinkedAttribute *la;
+};
 
 struct replmd_replicated_request {
        struct ldb_module *module;
-       struct ldb_handle *handle;
-       struct ldb_request *orig_req;
+       struct ldb_request *req;
 
        const struct dsdb_schema *schema;
 
@@ -63,59 +68,29 @@ struct replmd_replicated_request {
 
        uint32_t index_current;
 
-       struct {
-               TALLOC_CTX *mem_ctx;
-               struct ldb_request *search_req;
-               struct ldb_message *search_msg;
-               int search_ret;
-               struct ldb_request *change_req;
-               int change_ret;
-       } sub;
+       struct ldb_message *search_msg;
 };
 
-static struct replmd_replicated_request *replmd_replicated_init_handle(struct ldb_module *module,
-                                                                      struct ldb_request *req,
-                                                                      struct dsdb_extended_replicated_objects *objs)
+/*
+  created a replmd_replicated_request context
+ */
+static struct replmd_replicated_request *replmd_ctx_init(struct ldb_module *module,
+                                                        struct ldb_request *req)
 {
-       struct replmd_replicated_request *ar;
-       struct ldb_handle *h;
-       const struct dsdb_schema *schema;
+       struct ldb_context *ldb;
+       struct replmd_replicated_request *ac;
 
-       schema = dsdb_get_schema(module->ldb);
-       if (!schema) {
-               ldb_debug_set(module->ldb, LDB_DEBUG_FATAL,
-                             "replmd_replicated_init_handle: no loaded schema found\n");
-               return NULL;
-       }
+       ldb = ldb_module_get_ctx(module);
 
-       h = talloc_zero(req, struct ldb_handle);
-       if (h == NULL) {
-               ldb_set_errstring(module->ldb, "Out of Memory");
+       ac = talloc_zero(req, struct replmd_replicated_request);
+       if (ac == NULL) {
+               ldb_oom(ldb);
                return NULL;
        }
 
-       h->module       = module;
-       h->state        = LDB_ASYNC_PENDING;
-       h->status       = LDB_SUCCESS;
-
-       ar = talloc_zero(h, struct replmd_replicated_request);
-       if (ar == NULL) {
-               ldb_set_errstring(module->ldb, "Out of Memory");
-               talloc_free(h);
-               return NULL;
-       }
-
-       h->private_data = ar;
-
-       ar->module      = module;
-       ar->handle      = h;
-       ar->orig_req    = req;
-       ar->schema      = schema;
-       ar->objs        = objs;
-
-       req->handle = h;
-
-       return ar;
+       ac->module = module;
+       ac->req = req;
+       return ac;
 }
 
 /*
@@ -127,16 +102,16 @@ static int add_time_element(struct ldb_message *msg, const char *attr, time_t t)
        char *s;
 
        if (ldb_msg_find_element(msg, attr) != NULL) {
-               return 0;
+               return LDB_SUCCESS;
        }
 
        s = ldb_timestring(msg, t);
        if (s == NULL) {
-               return -1;
+               return LDB_ERR_OPERATIONS_ERROR;
        }
 
-       if (ldb_msg_add_string(msg, attr, s) != 0) {
-               return -1;
+       if (ldb_msg_add_string(msg, attr, s) != LDB_SUCCESS) {
+               return LDB_ERR_OPERATIONS_ERROR;
        }
 
        el = ldb_msg_find_element(msg, attr);
@@ -144,7 +119,7 @@ static int add_time_element(struct ldb_message *msg, const char *attr, time_t t)
           is ignored */
        el->flags = LDB_FLAG_MOD_REPLACE;
 
-       return 0;
+       return LDB_SUCCESS;
 }
 
 /*
@@ -155,11 +130,11 @@ static int add_uint64_element(struct ldb_message *msg, const char *attr, uint64_
        struct ldb_message_element *el;
 
        if (ldb_msg_find_element(msg, attr) != NULL) {
-               return 0;
+               return LDB_SUCCESS;
        }
 
-       if (ldb_msg_add_fmt(msg, attr, "%llu", (unsigned long long)v) != 0) {
-               return -1;
+       if (ldb_msg_add_fmt(msg, attr, "%llu", (unsigned long long)v) != LDB_SUCCESS) {
+               return LDB_ERR_OPERATIONS_ERROR;
        }
 
        el = ldb_msg_find_element(msg, attr);
@@ -167,7 +142,7 @@ static int add_uint64_element(struct ldb_message *msg, const char *attr, uint64_
           is ignored */
        el->flags = LDB_FLAG_MOD_REPLACE;
 
-       return 0;
+       return LDB_SUCCESS;
 }
 
 static int replmd_replPropertyMetaData1_attid_sort(const struct replPropertyMetaData1 *m1,
@@ -239,34 +214,40 @@ static void replmd_ldb_message_sort(struct ldb_message *msg,
                  discard_const_p(void, schema), (ldb_qsort_cmp_fn_t)replmd_ldb_message_element_attid_sort);
 }
 
-static int replmd_prepare_originating(struct ldb_module *module, struct ldb_request *req,
-                                     struct ldb_dn *dn, const char *fn_name,
-                                     int (*fn)(struct ldb_module *,
-                                               struct ldb_request *,
-                                               const struct dsdb_schema *))
+static int replmd_op_callback(struct ldb_request *req, struct ldb_reply *ares)
 {
-       const struct dsdb_schema *schema;
-       /* do not manipulate our control entries */
-       if (ldb_dn_is_special(dn)) {
-               return ldb_next_request(module, req);
+       struct ldb_context *ldb;
+       struct replmd_replicated_request *ac;
+
+       ac = talloc_get_type(req->context, struct replmd_replicated_request);
+       ldb = ldb_module_get_ctx(ac->module);
+
+       if (!ares) {
+               return ldb_module_done(ac->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
+       }
+       if (ares->error != LDB_SUCCESS) {
+               return ldb_module_done(ac->req, ares->controls,
+                                       ares->response, ares->error);
        }
 
-       schema = dsdb_get_schema(module->ldb);
-       if (!schema) {
-               ldb_debug_set(module->ldb, LDB_DEBUG_FATAL,
-                             "%s: no dsdb_schema loaded",
-                             fn_name);
-               return LDB_ERR_CONSTRAINT_VIOLATION;
+       if (ares->type != LDB_REPLY_DONE) {
+               ldb_set_errstring(ldb,
+                                 "invalid ldb_reply_type in callback");
+               talloc_free(ares);
+               return ldb_module_done(ac->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
        }
 
-       return fn(module, req, schema);
+       return ldb_module_done(ac->req, ares->controls,
+                               ares->response, LDB_SUCCESS);
 }
 
-static int replmd_add_originating(struct ldb_module *module,
-                                 struct ldb_request *req,
-                                 const struct dsdb_schema *schema)
+static int replmd_add(struct ldb_module *module, struct ldb_request *req)
 {
+       struct ldb_context *ldb;
+       struct replmd_replicated_request *ac;
+       const struct dsdb_schema *schema;
        enum ndr_err_code ndr_err;
        struct ldb_request *down_req;
        struct ldb_message *msg;
@@ -283,16 +264,37 @@ static int replmd_add_originating(struct ldb_module *module,
        int ret;
        uint32_t i, ni=0;
 
-       ldb_debug(module->ldb, LDB_DEBUG_TRACE, "replmd_add_originating\n");
+       /* do not manipulate our control entries */
+       if (ldb_dn_is_special(req->op.add.message->dn)) {
+               return ldb_next_request(module, req);
+       }
+
+       ldb = ldb_module_get_ctx(module);
+
+       ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_add\n");
+
+       schema = dsdb_get_schema(ldb);
+       if (!schema) {
+               ldb_debug_set(ldb, LDB_DEBUG_FATAL,
+                             "replmd_add: no dsdb_schema loaded");
+               return LDB_ERR_CONSTRAINT_VIOLATION;
+       }
+
+       ac = replmd_ctx_init(module, req);
+       if (!ac) {
+               return LDB_ERR_OPERATIONS_ERROR;
+       }
 
-       if (ldb_msg_find_element(req->op.add.message, "objectGUID")) {
-               ldb_debug_set(module->ldb, LDB_DEBUG_ERROR,
-                             "replmd_add_originating: it's not allowed to add an object with objectGUID\n");
+       ac->schema = schema;
+
+       if (ldb_msg_find_element(req->op.add.message, "objectGUID") != NULL) {
+               ldb_debug_set(ldb, LDB_DEBUG_ERROR,
+                             "replmd_add: it's not allowed to add an object with objectGUID\n");
                return LDB_ERR_UNWILLING_TO_PERFORM;
        }
 
        /* Get a sequence number from the backend */
-       ret = ldb_sequence_number(module->ldb, LDB_SEQ_NEXT, &seq_num);
+       ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, &seq_num);
        if (ret != LDB_SUCCESS) {
                return ret;
        }
@@ -300,27 +302,18 @@ static int replmd_add_originating(struct ldb_module *module,
        /* a new GUID */
        guid = GUID_random();
 
-       /* get our invicationId */
-       our_invocation_id = samdb_ntds_invocation_id(module->ldb);
+       /* get our invocationId */
+       our_invocation_id = samdb_ntds_invocation_id(ldb);
        if (!our_invocation_id) {
-               ldb_debug_set(module->ldb, LDB_DEBUG_ERROR,
-                             "replmd_add_originating: unable to find invocationId\n");
+               ldb_debug_set(ldb, LDB_DEBUG_ERROR,
+                             "replmd_add: unable to find invocationId\n");
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
-       /* create a copy of the request */
-       down_req = talloc(req, struct ldb_request);
-       if (down_req == NULL) {
-               ldb_oom(module->ldb);
-               return LDB_ERR_OPERATIONS_ERROR;
-       }
-       *down_req = *req;
-
        /* we have to copy the message as the caller might have it as a const */
-       down_req->op.add.message = msg = ldb_msg_copy_shallow(down_req, req->op.add.message);
+       msg = ldb_msg_copy_shallow(ac, req->op.add.message);
        if (msg == NULL) {
-               talloc_free(down_req);
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
@@ -328,7 +321,6 @@ static int replmd_add_originating(struct ldb_module *module,
        unix_to_nt_time(&now, t);
        time_str = ldb_timestring(msg, t);
        if (!time_str) {
-               talloc_free(down_req);
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
@@ -346,8 +338,7 @@ static int replmd_add_originating(struct ldb_module *module,
         */
        ret = ldb_msg_add_string(msg, "whenCreated", time_str);
        if (ret != LDB_SUCCESS) {
-               talloc_free(down_req);
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
@@ -359,8 +350,7 @@ static int replmd_add_originating(struct ldb_module *module,
                                               struct replPropertyMetaData1,
                                               nmd.ctr.ctr1.count);
        if (!nmd.ctr.ctr1.array) {
-               talloc_free(down_req);
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
@@ -373,10 +363,9 @@ static int replmd_add_originating(struct ldb_module *module,
 
                sa = dsdb_attribute_by_lDAPDisplayName(schema, e->name);
                if (!sa) {
-                       ldb_debug_set(module->ldb, LDB_DEBUG_ERROR,
-                                     "replmd_add_originating: attribute '%s' not defined in schema\n",
+                       ldb_debug_set(ldb, LDB_DEBUG_ERROR,
+                                     "replmd_add: attribute '%s' not defined in schema\n",
                                      e->name);
-                       talloc_free(down_req);
                        return LDB_ERR_NO_SUCH_ATTRIBUTE;
                }
 
@@ -414,16 +403,15 @@ static int replmd_add_originating(struct ldb_module *module,
                                       &guid,
                                       (ndr_push_flags_fn_t)ndr_push_GUID);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
        ndr_err = ndr_push_struct_blob(&nmd_value, msg, 
-                                      lp_iconv_convenience(ldb_get_opaque(module->ldb, "loadparm")),
+                                      lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")),
                                       &nmd,
                                       (ndr_push_flags_fn_t)ndr_push_replPropertyMetaDataBlob);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
-               talloc_free(down_req);
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
@@ -432,32 +420,27 @@ static int replmd_add_originating(struct ldb_module *module,
         */
        ret = ldb_msg_add_value(msg, "objectGUID", &guid_value, NULL);
        if (ret != LDB_SUCCESS) {
-               talloc_free(down_req);
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
        ret = ldb_msg_add_string(msg, "whenChanged", time_str);
        if (ret != LDB_SUCCESS) {
-               talloc_free(down_req);
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
-       ret = samdb_msg_add_uint64(module->ldb, msg, msg, "uSNCreated", seq_num);
+       ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNCreated", seq_num);
        if (ret != LDB_SUCCESS) {
-               talloc_free(down_req);
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
-       ret = samdb_msg_add_uint64(module->ldb, msg, msg, "uSNChanged", seq_num);
+       ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNChanged", seq_num);
        if (ret != LDB_SUCCESS) {
-               talloc_free(down_req);
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
        ret = ldb_msg_add_value(msg, "replPropertyMetaData", &nmd_value, NULL);
        if (ret != LDB_SUCCESS) {
-               talloc_free(down_req);
-               ldb_oom(module->ldb);
+               ldb_oom(ldb);
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
@@ -466,49 +449,235 @@ static int replmd_add_originating(struct ldb_module *module,
         */
        replmd_ldb_message_sort(msg, schema);
 
-       ldb_set_timeout_from_prev_req(module->ldb, req, down_req);
+       ret = ldb_build_add_req(&down_req, ldb, ac,
+                               msg,
+                               req->controls,
+                               ac, replmd_op_callback,
+                               req);
+       if (ret != LDB_SUCCESS) {
+               return ret;
+       }
 
        /* go on with the call chain */
-       ret = ldb_next_request(module, down_req);
+       return ldb_next_request(module, down_req);
+}
 
-       /* do not free down_req as the call results may be linked to it,
-        * it will be freed when the upper level request get freed */
-       if (ret == LDB_SUCCESS) {
-               req->handle = down_req->handle;
+
+/*
+ * update the replPropertyMetaData for one element
+ */
+static int replmd_update_rpmd_element(struct ldb_context *ldb, 
+                                     struct ldb_message *msg,
+                                     struct ldb_message_element *el,
+                                     struct replPropertyMetaDataBlob *omd,
+                                     struct dsdb_schema *schema,
+                                     uint64_t *seq_num,
+                                     const struct GUID *our_invocation_id,
+                                     NTTIME now)
+{
+       int i;
+       const struct dsdb_attribute *a;
+       struct replPropertyMetaData1 *md1;
+
+       a = dsdb_attribute_by_lDAPDisplayName(schema, el->name);
+       if (a == NULL) {
+               DEBUG(0,(__location__ ": Unable to find attribute %s in schema\n",
+                        el->name));
+               return LDB_ERR_OPERATIONS_ERROR;
        }
 
-       return ret;
+       if ((a->systemFlags & 0x00000001) || (a->systemFlags & 0x00000004)) {
+               /* if the attribute is not replicated (0x00000001)
+                * or constructed (0x00000004) it has no metadata
+                */
+               return LDB_SUCCESS;
+       }
+
+       for (i=0; i<omd->ctr.ctr1.count; i++) {
+               if (a->attributeID_id == omd->ctr.ctr1.array[i].attid) break;
+       }
+       if (i == omd->ctr.ctr1.count) {
+               /* we need to add a new one */
+               omd->ctr.ctr1.array = talloc_realloc(msg, omd->ctr.ctr1.array, 
+                                                    struct replPropertyMetaData1, omd->ctr.ctr1.count+1);
+               if (omd->ctr.ctr1.array == NULL) {
+                       ldb_oom(ldb);
+                       return LDB_ERR_OPERATIONS_ERROR;
+               }
+               omd->ctr.ctr1.count++;
+               ZERO_STRUCT(omd->ctr.ctr1.array[i]);
+       }
+
+       /* Get a new sequence number from the backend. We only do this
+        * if we have a change that requires a new
+        * replPropertyMetaData element 
+        */
+       if (*seq_num == 0) {
+               int ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, seq_num);
+               if (ret != LDB_SUCCESS) {
+                       return LDB_ERR_OPERATIONS_ERROR;
+               }
+       }
+
+       md1 = &omd->ctr.ctr1.array[i];
+       md1->version++;
+       md1->attid                     = a->attributeID_id;
+       md1->originating_change_time   = now;
+       md1->originating_invocation_id = *our_invocation_id;
+       md1->originating_usn           = *seq_num;
+       md1->local_usn                 = *seq_num;
+       
+       return LDB_SUCCESS;
 }
 
-static int replmd_add(struct ldb_module *module, struct ldb_request *req)
+/*
+ * update the replPropertyMetaData object each time we modify an
+ * object. This is needed for DRS replication, as the merge on the
+ * client is based on this object 
+ */
+static int replmd_update_rpmd(struct ldb_context *ldb, struct ldb_message *msg,
+                             uint64_t *seq_num)
 {
-       return replmd_prepare_originating(module, req, req->op.add.message->dn,
-                                         "replmd_add", replmd_add_originating);
+       const struct ldb_val *omd_value;
+       enum ndr_err_code ndr_err;
+       struct replPropertyMetaDataBlob omd;
+       int i;
+       struct dsdb_schema *schema;
+       time_t t = time(NULL);
+       NTTIME now;
+       const struct GUID *our_invocation_id;
+       int ret;
+       const char *attrs[] = { "replPropertyMetaData" , NULL };
+       struct ldb_result *res;
+
+       our_invocation_id = samdb_ntds_invocation_id(ldb);
+       if (!our_invocation_id) {
+               /* this happens during an initial vampire while
+                  updating the schema */
+               DEBUG(5,("No invocationID - skipping replPropertyMetaData update\n"));
+               return LDB_SUCCESS;
+       }
+
+       unix_to_nt_time(&now, t);
+
+       /* search for the existing replPropertyMetaDataBlob */
+       ret = ldb_search(ldb, msg, &res, msg->dn, LDB_SCOPE_BASE, attrs, NULL);
+       if (ret != LDB_SUCCESS || res->count < 1) {
+               DEBUG(0,(__location__ ": Object %s failed to find replPropertyMetaData\n",
+                        ldb_dn_get_linearized(msg->dn)));
+               return LDB_ERR_OPERATIONS_ERROR;
+       }
+               
+
+       omd_value = ldb_msg_find_ldb_val(res->msgs[0], "replPropertyMetaData");
+       if (!omd_value) {
+               DEBUG(0,(__location__ ": Object %s does not have a replPropertyMetaData attribute\n",
+                        ldb_dn_get_linearized(msg->dn)));
+               return LDB_ERR_OPERATIONS_ERROR;
+       }
+
+       ndr_err = ndr_pull_struct_blob(omd_value, msg,
+                                      lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")), &omd,
+                                      (ndr_pull_flags_fn_t)ndr_pull_replPropertyMetaDataBlob);
+       if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+               DEBUG(0,(__location__ ": Failed to parse replPropertyMetaData for %s\n",
+                        ldb_dn_get_linearized(msg->dn)));
+               return LDB_ERR_OPERATIONS_ERROR;
+       }
+
+       if (omd.version != 1) {
+               DEBUG(0,(__location__ ": bad version %u in replPropertyMetaData for %s\n",
+                        omd.version, ldb_dn_get_linearized(msg->dn)));
+               return LDB_ERR_OPERATIONS_ERROR;
+       }
+
+       schema = dsdb_get_schema(ldb);
+
+       for (i=0; i<msg->num_elements; i++) {
+               ret = replmd_update_rpmd_element(ldb, msg, &msg->elements[i], &omd, schema, seq_num, 
+                                                our_invocation_id, now);
+               if (ret != LDB_SUCCESS) {
+                       return ret;
+               }
+       }
+
+       /*
+        * replmd_update_rpmd_element has done an update if the
+        * seq_num is set
+        */
+       if (*seq_num != 0) {
+               struct ldb_val *md_value;
+               struct ldb_message_element *el;
+
+               md_value = talloc(msg, struct ldb_val);
+               if (md_value == NULL) {
+                       ldb_oom(ldb);
+                       return LDB_ERR_OPERATIONS_ERROR;
+               }
+
+               ndr_err = ndr_push_struct_blob(md_value, msg, 
+                                              lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")),
+                                              &omd,
+                                              (ndr_push_flags_fn_t)ndr_push_replPropertyMetaDataBlob);
+               if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+                       DEBUG(0,(__location__ ": Failed to marshall replPropertyMetaData for %s\n",
+                                ldb_dn_get_linearized(msg->dn)));
+                       return LDB_ERR_OPERATIONS_ERROR;
+               }
+
+               ret = ldb_msg_add_empty(msg, "replPropertyMetaData", LDB_FLAG_MOD_REPLACE, &el);
+               if (ret != LDB_SUCCESS) {
+                       DEBUG(0,(__location__ ": Failed to add updated replPropertyMetaData %s\n",
+                                ldb_dn_get_linearized(msg->dn)));
+                       return ret;
+               }
+
+               el->num_values = 1;
+               el->values = md_value;
+       }
+
+       return LDB_SUCCESS;     
 }
 
-static int replmd_modify_originating(struct ldb_module *module,
-                                    struct ldb_request *req,
-                                    const struct dsdb_schema *schema)
+
+static int replmd_modify(struct ldb_module *module, struct ldb_request *req)
 {
+       struct ldb_context *ldb;
+       struct replmd_replicated_request *ac;
+       const struct dsdb_schema *schema;
        struct ldb_request *down_req;
        struct ldb_message *msg;
        int ret;
        time_t t = time(NULL);
-       uint64_t seq_num;
+       uint64_t seq_num = 0;
+
+       /* do not manipulate our control entries */
+       if (ldb_dn_is_special(req->op.mod.message->dn)) {
+               return ldb_next_request(module, req);
+       }
 
-       ldb_debug(module->ldb, LDB_DEBUG_TRACE, "replmd_modify_originating\n");
+       ldb = ldb_module_get_ctx(module);
 
-       down_req = talloc(req, struct ldb_request);
-       if (down_req == NULL) {
+       ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_modify\n");
+
+       schema = dsdb_get_schema(ldb);
+       if (!schema) {
+               ldb_debug_set(ldb, LDB_DEBUG_FATAL,
+                             "replmd_modify: no dsdb_schema loaded");
+               return LDB_ERR_CONSTRAINT_VIOLATION;
+       }
+
+       ac = replmd_ctx_init(module, req);
+       if (!ac) {
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
-       *down_req = *req;
+       ac->schema = schema;
 
        /* we have to copy the message as the caller might have it as a const */
-       down_req->op.mod.message = msg = ldb_msg_copy_shallow(down_req, req->op.mod.message);
+       msg = ldb_msg_copy_shallow(ac, req->op.mod.message);
        if (msg == NULL) {
-               talloc_free(down_req);
+               talloc_free(ac);
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
@@ -521,21 +690,11 @@ static int replmd_modify_originating(struct ldb_module *module,
         *   if the caller set values to the same value
         *   ignore the attribute, return success when no
         *   attribute was changed
-        * - calculate the new replPropertyMetaData attribute
         */
 
-       if (add_time_element(msg, "whenChanged", t) != 0) {
-               talloc_free(down_req);
-               return LDB_ERR_OPERATIONS_ERROR;
-       }
-
-       /* Get a sequence number from the backend */
-       ret = ldb_sequence_number(module->ldb, LDB_SEQ_NEXT, &seq_num);
-       if (ret == LDB_SUCCESS) {
-               if (add_uint64_element(msg, "uSNChanged", seq_num) != 0) {
-                       talloc_free(down_req);
-                       return LDB_ERR_OPERATIONS_ERROR;
-               }
+       ret = replmd_update_rpmd(ldb, msg, &seq_num);
+       if (ret != LDB_SUCCESS) {
+               return ret;
        }
 
        /* TODO:
@@ -543,96 +702,88 @@ static int replmd_modify_originating(struct ldb_module *module,
         * - replace the old object with the newly constructed one
         */
 
-       ldb_set_timeout_from_prev_req(module->ldb, req, down_req);
-
-       /* go on with the call chain */
-       ret = ldb_next_request(module, down_req);
-
-       /* do not free down_req as the call results may be linked to it,
-        * it will be freed when the upper level request get freed */
-       if (ret == LDB_SUCCESS) {
-               req->handle = down_req->handle;
+       ret = ldb_build_mod_req(&down_req, ldb, ac,
+                               msg,
+                               req->controls,
+                               ac, replmd_op_callback,
+                               req);
+       if (ret != LDB_SUCCESS) {
+               return ret;
        }
+       talloc_steal(down_req, msg);
 
-       return ret;
-}
-
-static int replmd_modify(struct ldb_module *module, struct ldb_request *req)
-{
-       return replmd_prepare_originating(module, req, req->op.mod.message->dn,
-                                         "replmd_modify", replmd_modify_originating);
-}
-
-static int replmd_replicated_request_reply_helper(struct replmd_replicated_request *ar, int ret)
-{
-       struct ldb_reply *ares = NULL;
-
-       ar->handle->status = ret;
-       ar->handle->state = LDB_ASYNC_DONE;
+       /* we only change whenChanged and uSNChanged if the seq_num
+          has changed */
+       if (seq_num != 0) {
+               if (add_time_element(msg, "whenChanged", t) != LDB_SUCCESS) {
+                       talloc_free(ac);
+                       return LDB_ERR_OPERATIONS_ERROR;
+               }
 
-       if (!ar->orig_req->callback) {
-               return LDB_SUCCESS;
-       }
-       
-       /* we're done and need to report the success to the caller */
-       ares = talloc_zero(ar, struct ldb_reply);
-       if (!ares) {
-               ar->handle->status = LDB_ERR_OPERATIONS_ERROR;
-               ar->handle->state = LDB_ASYNC_DONE;
-               return LDB_ERR_OPERATIONS_ERROR;
+               if (add_uint64_element(msg, "uSNChanged", seq_num) != LDB_SUCCESS) {
+                       talloc_free(ac);
+                       return LDB_ERR_OPERATIONS_ERROR;
+               }
        }
 
-       ares->type      = LDB_REPLY_EXTENDED;
-       ares->response  = NULL;
-
-       return ar->orig_req->callback(ar->module->ldb, ar->orig_req->context, ares);
-}
-
-static int replmd_replicated_request_done(struct replmd_replicated_request *ar)
-{
-       return replmd_replicated_request_reply_helper(ar, LDB_SUCCESS);
+       /* go on with the call chain */
+       return ldb_next_request(module, down_req);
 }
 
 static int replmd_replicated_request_error(struct replmd_replicated_request *ar, int ret)
 {
-       return replmd_replicated_request_reply_helper(ar, ret);
+       return ret;
 }
 
 static int replmd_replicated_request_werror(struct replmd_replicated_request *ar, WERROR status)
 {
        int ret = LDB_ERR_OTHER;
        /* TODO: do some error mapping */
-       return replmd_replicated_request_reply_helper(ar, ret);
+       return ret;
 }
 
 static int replmd_replicated_apply_next(struct replmd_replicated_request *ar);
 
-static int replmd_replicated_apply_add_callback(struct ldb_context *ldb,
-                                               void *private_data,
+static int replmd_replicated_apply_add_callback(struct ldb_request *req,
                                                struct ldb_reply *ares)
 {
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       struct replmd_replicated_request *ar = talloc_get_type(private_data,
+       struct ldb_context *ldb;
+       struct replmd_replicated_request *ar = talloc_get_type(req->context,
                                               struct replmd_replicated_request);
+       int ret;
 
-       ar->sub.change_ret = ldb_wait(ar->sub.search_req->handle, LDB_WAIT_ALL);
-       if (ar->sub.change_ret != LDB_SUCCESS) {
-               return replmd_replicated_request_error(ar, ar->sub.change_ret);
+       ldb = ldb_module_get_ctx(ar->module);
+
+       if (!ares) {
+               return ldb_module_done(ar->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
+       }
+       if (ares->error != LDB_SUCCESS) {
+               return ldb_module_done(ar->req, ares->controls,
+                                       ares->response, ares->error);
        }
 
-       talloc_free(ar->sub.mem_ctx);
-       ZERO_STRUCT(ar->sub);
+       if (ares->type != LDB_REPLY_DONE) {
+               ldb_set_errstring(ldb, "Invalid reply type\n!");
+               return ldb_module_done(ar->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
+       }
 
+       talloc_free(ares);
        ar->index_current++;
 
-       return replmd_replicated_apply_next(ar);
-#else
+       ret = replmd_replicated_apply_next(ar);
+       if (ret != LDB_SUCCESS) {
+               return ldb_module_done(ar->req, NULL, NULL, ret);
+       }
+
        return LDB_SUCCESS;
-#endif
 }
 
 static int replmd_replicated_apply_add(struct replmd_replicated_request *ar)
 {
+       struct ldb_context *ldb;
+       struct ldb_request *change_req;
        enum ndr_err_code ndr_err;
        struct ldb_message *msg;
        struct replPropertyMetaDataBlob *md;
@@ -650,10 +801,11 @@ static int replmd_replicated_apply_add(struct replmd_replicated_request *ar)
         *       same name exist
         */
 
+       ldb = ldb_module_get_ctx(ar->module);
        msg = ar->objs->objects[ar->index_current].msg;
        md = ar->objs->objects[ar->index_current].meta_data;
 
-       ret = ldb_sequence_number(ar->module->ldb, LDB_SEQ_NEXT, &seq_num);
+       ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, &seq_num);
        if (ret != LDB_SUCCESS) {
                return replmd_replicated_request_error(ar, ret);
        }
@@ -668,12 +820,12 @@ static int replmd_replicated_apply_add(struct replmd_replicated_request *ar)
                return replmd_replicated_request_error(ar, ret);
        }
 
-       ret = samdb_msg_add_uint64(ar->module->ldb, msg, msg, "uSNCreated", seq_num);
+       ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNCreated", seq_num);
        if (ret != LDB_SUCCESS) {
                return replmd_replicated_request_error(ar, ret);
        }
 
-       ret = samdb_msg_add_uint64(ar->module->ldb, msg, msg, "uSNChanged", seq_num);
+       ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNChanged", seq_num);
        if (ret != LDB_SUCCESS) {
                return replmd_replicated_request_error(ar, ret);
        }
@@ -685,7 +837,7 @@ static int replmd_replicated_apply_add(struct replmd_replicated_request *ar)
                md->ctr.ctr1.array[i].local_usn = seq_num;
        }
        ndr_err = ndr_push_struct_blob(&md_value, msg, 
-                                      lp_iconv_convenience(ldb_get_opaque(ar->module->ldb, "loadparm")),
+                                      lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")),
                                       md,
                                       (ndr_push_flags_fn_t)ndr_push_replPropertyMetaDataBlob);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
@@ -699,39 +851,23 @@ static int replmd_replicated_apply_add(struct replmd_replicated_request *ar)
 
        replmd_ldb_message_sort(msg, ar->schema);
 
-       ret = ldb_build_add_req(&ar->sub.change_req,
-                               ar->module->ldb,
-                               ar->sub.mem_ctx,
+       if (DEBUGLVL(4)) {
+               char *s = ldb_ldif_message_string(ldb, ar, LDB_CHANGETYPE_ADD, msg);
+               DEBUG(4, ("DRS replication add message:\n%s\n", s));
+               talloc_free(s);
+       }
+
+       ret = ldb_build_add_req(&change_req,
+                               ldb,
+                               ar,
                                msg,
                                ar->controls,
                                ar,
-                               replmd_replicated_apply_add_callback);
+                               replmd_replicated_apply_add_callback,
+                               ar->req);
        if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
 
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       return ldb_next_request(ar->module, ar->sub.change_req);
-#else
-       ret = ldb_next_request(ar->module, ar->sub.change_req);
-       if (ret != LDB_SUCCESS) {
-               ldb_asprintf_errstring(ar->module->ldb, "Failed to add replicated object %s: %s", ldb_dn_get_linearized(ar->sub.change_req->op.add.message->dn), 
-                                      ldb_errstring(ar->module->ldb));
-               return replmd_replicated_request_error(ar, ret);
-       }
-
-       ar->sub.change_ret = ldb_wait(ar->sub.change_req->handle, LDB_WAIT_ALL);
-       if (ar->sub.change_ret != LDB_SUCCESS) {
-               ldb_asprintf_errstring(ar->module->ldb, "Failed while waiting on add replicated object %s: %s", ldb_dn_get_linearized(ar->sub.change_req->op.add.message->dn), 
-                                      ldb_errstring(ar->module->ldb));
-               return replmd_replicated_request_error(ar, ar->sub.change_ret);
-       }
-
-       talloc_free(ar->sub.mem_ctx);
-       ZERO_STRUCT(ar->sub);
-
-       ar->index_current++;
-
-       return LDB_SUCCESS;
-#endif
+       return ldb_next_request(ar->module, change_req);
 }
 
 static int replmd_replPropertyMetaData1_conflict_compare(struct replPropertyMetaData1 *m1,
@@ -755,35 +891,46 @@ static int replmd_replPropertyMetaData1_conflict_compare(struct replPropertyMeta
        return m1->originating_usn - m2->originating_usn;
 }
 
-static int replmd_replicated_apply_merge_callback(struct ldb_context *ldb,
-                                                 void *private_data,
+static int replmd_replicated_apply_merge_callback(struct ldb_request *req,
                                                  struct ldb_reply *ares)
 {
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       struct replmd_replicated_request *ar = talloc_get_type(private_data,
+       struct ldb_context *ldb;
+       struct replmd_replicated_request *ar = talloc_get_type(req->context,
                                               struct replmd_replicated_request);
+       int ret;
 
-       ret = ldb_next_request(ar->module, ar->sub.change_req);
-       if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
+       ldb = ldb_module_get_ctx(ar->module);
 
-       ar->sub.change_ret = ldb_wait(ar->sub.search_req->handle, LDB_WAIT_ALL);
-       if (ar->sub.change_ret != LDB_SUCCESS) {
-               return replmd_replicated_request_error(ar, ar->sub.change_ret);
+       if (!ares) {
+               return ldb_module_done(ar->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
+       }
+       if (ares->error != LDB_SUCCESS) {
+               return ldb_module_done(ar->req, ares->controls,
+                                       ares->response, ares->error);
        }
 
-       talloc_free(ar->sub.mem_ctx);
-       ZERO_STRUCT(ar->sub);
+       if (ares->type != LDB_REPLY_DONE) {
+               ldb_set_errstring(ldb, "Invalid reply type\n!");
+               return ldb_module_done(ar->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
+       }
 
+       talloc_free(ares);
        ar->index_current++;
 
+       ret = replmd_replicated_apply_next(ar);
+       if (ret != LDB_SUCCESS) {
+               return ldb_module_done(ar->req, NULL, NULL, ret);
+       }
+
        return LDB_SUCCESS;
-#else
-       return LDB_SUCCESS;
-#endif
 }
 
 static int replmd_replicated_apply_merge(struct replmd_replicated_request *ar)
 {
+       struct ldb_context *ldb;
+       struct ldb_request *change_req;
        enum ndr_err_code ndr_err;
        struct ldb_message *msg;
        struct replPropertyMetaDataBlob *rmd;
@@ -796,33 +943,33 @@ static int replmd_replicated_apply_merge(struct replmd_replicated_request *ar)
        uint64_t seq_num;
        int ret;
 
+       ldb = ldb_module_get_ctx(ar->module);
        msg = ar->objs->objects[ar->index_current].msg;
        rmd = ar->objs->objects[ar->index_current].meta_data;
        ZERO_STRUCT(omd);
        omd.version = 1;
 
        /*
-        * TODO: add rename conflict handling
+        * TODO: check repl data is correct after a rename
         */
-       if (ldb_dn_compare(msg->dn, ar->sub.search_msg->dn) != 0) {
-               ldb_debug_set(ar->module->ldb, LDB_DEBUG_FATAL, "replmd_replicated_apply_merge[%u]: rename not supported",
-                             ar->index_current);
-               ldb_debug(ar->module->ldb, LDB_DEBUG_FATAL, "%s => %s\n",
-                         ldb_dn_get_linearized(ar->sub.search_msg->dn),
+       if (ldb_dn_compare(msg->dn, ar->search_msg->dn) != 0) {
+               ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_replicated_request rename %s => %s\n",
+                         ldb_dn_get_linearized(ar->search_msg->dn),
                          ldb_dn_get_linearized(msg->dn));
-               return replmd_replicated_request_werror(ar, WERR_NOT_SUPPORTED);
-       }
-
-       ret = ldb_sequence_number(ar->module->ldb, LDB_SEQ_NEXT, &seq_num);
-       if (ret != LDB_SUCCESS) {
-               return replmd_replicated_request_error(ar, ret);
+               if (ldb_rename(ldb, ar->search_msg->dn, msg->dn) != LDB_SUCCESS) {
+                       ldb_debug(ldb, LDB_DEBUG_FATAL, "replmd_replicated_request rename %s => %s failed - %s\n",
+                                 ldb_dn_get_linearized(ar->search_msg->dn),
+                                 ldb_dn_get_linearized(msg->dn),
+                                 ldb_errstring(ldb));
+                       return replmd_replicated_request_werror(ar, WERR_DS_DRA_DB_ERROR);
+               }
        }
 
        /* find existing meta data */
-       omd_value = ldb_msg_find_ldb_val(ar->sub.search_msg, "replPropertyMetaData");
+       omd_value = ldb_msg_find_ldb_val(ar->search_msg, "replPropertyMetaData");
        if (omd_value) {
-               ndr_err = ndr_pull_struct_blob(omd_value, ar->sub.mem_ctx, 
-                                              lp_iconv_convenience(ldb_get_opaque(ar->module->ldb, "loadparm")), &omd,
+               ndr_err = ndr_pull_struct_blob(omd_value, ar,
+                                              lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")), &omd,
                                               (ndr_pull_flags_fn_t)ndr_pull_replPropertyMetaDataBlob);
                if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
                        NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
@@ -837,7 +984,7 @@ static int replmd_replicated_apply_merge(struct replmd_replicated_request *ar)
        ZERO_STRUCT(nmd);
        nmd.version = 1;
        nmd.ctr.ctr1.count = omd.ctr.ctr1.count + rmd->ctr.ctr1.count;
-       nmd.ctr.ctr1.array = talloc_array(ar->sub.mem_ctx,
+       nmd.ctr.ctr1.array = talloc_array(ar,
                                          struct replPropertyMetaData1,
                                          nmd.ctr.ctr1.count);
        if (!nmd.ctr.ctr1.array) return replmd_replicated_request_werror(ar, WERR_NOMEM);
@@ -852,8 +999,6 @@ static int replmd_replicated_apply_merge(struct replmd_replicated_request *ar)
        for (i=0; i < rmd->ctr.ctr1.count; i++) {
                bool found = false;
 
-               rmd->ctr.ctr1.array[i].local_usn = seq_num;
-
                for (j=0; j < ni; j++) {
                        int cmp;
 
@@ -906,7 +1051,7 @@ static int replmd_replicated_apply_merge(struct replmd_replicated_request *ar)
 
        /* create the meta data value */
        ndr_err = ndr_push_struct_blob(&nmd_value, msg, 
-                                      lp_iconv_convenience(ldb_get_opaque(ar->module->ldb, "loadparm")),
+                                      lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")),
                                       &nmd,
                                       (ndr_push_flags_fn_t)ndr_push_replPropertyMetaDataBlob);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
@@ -918,23 +1063,34 @@ static int replmd_replicated_apply_merge(struct replmd_replicated_request *ar)
         * check if some replicated attributes left, otherwise skip the ldb_modify() call
         */
        if (msg->num_elements == 0) {
-               ldb_debug(ar->module->ldb, LDB_DEBUG_TRACE, "replmd_replicated_apply_merge[%u]: skip replace\n",
+               ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_replicated_apply_merge[%u]: skip replace\n",
                          ar->index_current);
-               goto next_object;
+
+               ar->index_current++;
+               return replmd_replicated_apply_next(ar);
        }
 
-       ldb_debug(ar->module->ldb, LDB_DEBUG_TRACE, "replmd_replicated_apply_merge[%u]: replace %u attributes\n",
+       ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_replicated_apply_merge[%u]: replace %u attributes\n",
                  ar->index_current, msg->num_elements);
 
+       ret = ldb_sequence_number(ldb, LDB_SEQ_NEXT, &seq_num);
+       if (ret != LDB_SUCCESS) {
+               return replmd_replicated_request_error(ar, ret);
+       }
+
+       for (i=0; i<ni; i++) {
+               nmd.ctr.ctr1.array[i].local_usn = seq_num;
+       }
+
        /*
-        * when we now that we'll modify the record, add the whenChanged, uSNChanged
+        * when we know that we'll modify the record, add the whenChanged, uSNChanged
         * and replPopertyMetaData attributes
         */
        ret = ldb_msg_add_string(msg, "whenChanged", ar->objs->objects[ar->index_current].when_changed);
        if (ret != LDB_SUCCESS) {
                return replmd_replicated_request_error(ar, ret);
        }
-       ret = samdb_msg_add_uint64(ar->module->ldb, msg, msg, "uSNChanged", seq_num);
+       ret = samdb_msg_add_uint64(ldb, msg, msg, "uSNChanged", seq_num);
        if (ret != LDB_SUCCESS) {
                return replmd_replicated_request_error(ar, ret);
        }
@@ -950,150 +1106,133 @@ static int replmd_replicated_apply_merge(struct replmd_replicated_request *ar)
                msg->elements[i].flags = LDB_FLAG_MOD_REPLACE;
        }
 
-       ret = ldb_build_mod_req(&ar->sub.change_req,
-                               ar->module->ldb,
-                               ar->sub.mem_ctx,
+       if (DEBUGLVL(4)) {
+               char *s = ldb_ldif_message_string(ldb, ar, LDB_CHANGETYPE_MODIFY, msg);
+               DEBUG(4, ("DRS replication modify message:\n%s\n", s));
+               talloc_free(s);
+       }
+
+       ret = ldb_build_mod_req(&change_req,
+                               ldb,
+                               ar,
                                msg,
                                ar->controls,
                                ar,
-                               replmd_replicated_apply_merge_callback);
-       if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
-
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       return ldb_next_request(ar->module, ar->sub.change_req);
-#else
-       ret = ldb_next_request(ar->module, ar->sub.change_req);
+                               replmd_replicated_apply_merge_callback,
+                               ar->req);
        if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
 
-       ar->sub.change_ret = ldb_wait(ar->sub.change_req->handle, LDB_WAIT_ALL);
-       if (ar->sub.change_ret != LDB_SUCCESS) {
-               return replmd_replicated_request_error(ar, ar->sub.change_ret);
-       }
-
-next_object:
-       talloc_free(ar->sub.mem_ctx);
-       ZERO_STRUCT(ar->sub);
-
-       ar->index_current++;
-
-       return LDB_SUCCESS;
-#endif
+       return ldb_next_request(ar->module, change_req);
 }
 
-static int replmd_replicated_apply_search_callback(struct ldb_context *ldb,
-                                                  void *private_data,
+static int replmd_replicated_apply_search_callback(struct ldb_request *req,
                                                   struct ldb_reply *ares)
 {
-       struct replmd_replicated_request *ar = talloc_get_type(private_data,
+       struct replmd_replicated_request *ar = talloc_get_type(req->context,
                                               struct replmd_replicated_request);
-       bool is_done = false;
+       int ret;
+
+       if (!ares) {
+               return ldb_module_done(ar->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
+       }
+       if (ares->error != LDB_SUCCESS &&
+           ares->error != LDB_ERR_NO_SUCH_OBJECT) {
+               return ldb_module_done(ar->req, ares->controls,
+                                       ares->response, ares->error);
+       }
 
        switch (ares->type) {
        case LDB_REPLY_ENTRY:
-               ar->sub.search_msg = talloc_steal(ar->sub.mem_ctx, ares->message);
+               ar->search_msg = talloc_steal(ar, ares->message);
                break;
+
        case LDB_REPLY_REFERRAL:
                /* we ignore referrals */
                break;
-       case LDB_REPLY_EXTENDED:
-       case LDB_REPLY_DONE:
-               is_done = true;
-       }
 
-       talloc_free(ares);
-
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       if (is_done) {
-               ar->sub.search_ret = ldb_wait(ar->sub.search_req->handle, LDB_WAIT_ALL);
-               if (ar->sub.search_ret != LDB_SUCCESS) {
-                       return replmd_replicated_request_error(ar, ar->sub.search_ret);
+       case LDB_REPLY_DONE:
+               if (ar->search_msg != NULL) {
+                       ret = replmd_replicated_apply_merge(ar);
+               } else {
+                       ret = replmd_replicated_apply_add(ar);
                }
-               if (ar->sub.search_msg) {
-                       return replmd_replicated_apply_merge(ar);
+               if (ret != LDB_SUCCESS) {
+                       return ldb_module_done(ar->req, NULL, NULL, ret);
                }
-               return replmd_replicated_apply_add(ar);
        }
-#endif
+
+       talloc_free(ares);
        return LDB_SUCCESS;
 }
 
-static int replmd_replicated_apply_search(struct replmd_replicated_request *ar)
+static int replmd_replicated_uptodate_vector(struct replmd_replicated_request *ar);
+
+static int replmd_replicated_apply_next(struct replmd_replicated_request *ar)
 {
+       struct ldb_context *ldb;
        int ret;
        char *tmp_str;
        char *filter;
+       struct ldb_request *search_req;
+
+       if (ar->index_current >= ar->objs->num_objects) {
+               /* done with it, go to next stage */
+               return replmd_replicated_uptodate_vector(ar);
+       }
 
-       tmp_str = ldb_binary_encode(ar->sub.mem_ctx, ar->objs->objects[ar->index_current].guid_value);
+       ldb = ldb_module_get_ctx(ar->module);
+       ar->search_msg = NULL;
+
+       tmp_str = ldb_binary_encode(ar, ar->objs->objects[ar->index_current].guid_value);
        if (!tmp_str) return replmd_replicated_request_werror(ar, WERR_NOMEM);
 
-       filter = talloc_asprintf(ar->sub.mem_ctx, "(objectGUID=%s)", tmp_str);
+       filter = talloc_asprintf(ar, "(objectGUID=%s)", tmp_str);
        if (!filter) return replmd_replicated_request_werror(ar, WERR_NOMEM);
        talloc_free(tmp_str);
 
-       ret = ldb_build_search_req(&ar->sub.search_req,
-                                  ar->module->ldb,
-                                  ar->sub.mem_ctx,
+       ret = ldb_build_search_req(&search_req,
+                                  ldb,
+                                  ar,
                                   ar->objs->partition_dn,
                                   LDB_SCOPE_SUBTREE,
                                   filter,
                                   NULL,
                                   NULL,
                                   ar,
-                                  replmd_replicated_apply_search_callback);
+                                  replmd_replicated_apply_search_callback,
+                                  ar->req);
        if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
 
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       return ldb_next_request(ar->module, ar->sub.search_req);
-#else
-       ret = ldb_next_request(ar->module, ar->sub.search_req);
-       if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
-
-       ar->sub.search_ret = ldb_wait(ar->sub.search_req->handle, LDB_WAIT_ALL);
-       if (ar->sub.search_ret != LDB_SUCCESS && ar->sub.search_ret != LDB_ERR_NO_SUCH_OBJECT) {
-               return replmd_replicated_request_error(ar, ar->sub.search_ret);
-       }
-       if (ar->sub.search_msg) {
-               return replmd_replicated_apply_merge(ar);
-       }
-
-       return replmd_replicated_apply_add(ar);
-#endif
+       return ldb_next_request(ar->module, search_req);
 }
 
-static int replmd_replicated_apply_next(struct replmd_replicated_request *ar)
-{
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       if (ar->index_current >= ar->objs->num_objects) {
-               return replmd_replicated_uptodate_vector(ar);
-       }
-#endif
-
-       ar->sub.mem_ctx = talloc_new(ar);
-       if (!ar->sub.mem_ctx) return replmd_replicated_request_werror(ar, WERR_NOMEM);
-
-       return replmd_replicated_apply_search(ar);
-}
-
-static int replmd_replicated_uptodate_modify_callback(struct ldb_context *ldb,
-                                                     void *private_data,
+static int replmd_replicated_uptodate_modify_callback(struct ldb_request *req,
                                                      struct ldb_reply *ares)
 {
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       struct replmd_replicated_request *ar = talloc_get_type(private_data,
+       struct ldb_context *ldb;
+       struct replmd_replicated_request *ar = talloc_get_type(req->context,
                                               struct replmd_replicated_request);
+       ldb = ldb_module_get_ctx(ar->module);
 
-       ar->sub.change_ret = ldb_wait(ar->sub.search_req->handle, LDB_WAIT_ALL);
-       if (ar->sub.change_ret != LDB_SUCCESS) {
-               return replmd_replicated_request_error(ar, ar->sub.change_ret);
+       if (!ares) {
+               return ldb_module_done(ar->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
+       }
+       if (ares->error != LDB_SUCCESS) {
+               return ldb_module_done(ar->req, ares->controls,
+                                       ares->response, ares->error);
        }
 
-       talloc_free(ar->sub.mem_ctx);
-       ZERO_STRUCT(ar->sub);
+       if (ares->type != LDB_REPLY_DONE) {
+               ldb_set_errstring(ldb, "Invalid reply type\n!");
+               return ldb_module_done(ar->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
+       }
 
-       return replmd_replicated_request_done(ar);
-#else
-       return LDB_SUCCESS;
-#endif
+       talloc_free(ares);
+
+       return ldb_module_done(ar->req, NULL, NULL, LDB_SUCCESS);
 }
 
 static int replmd_drsuapi_DsReplicaCursor2_compare(const struct drsuapi_DsReplicaCursor2 *c1,
@@ -1104,6 +1243,8 @@ static int replmd_drsuapi_DsReplicaCursor2_compare(const struct drsuapi_DsReplic
 
 static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *ar)
 {
+       struct ldb_context *ldb;
+       struct ldb_request *change_req;
        enum ndr_err_code ndr_err;
        struct ldb_message *msg;
        struct replUpToDateVectorBlob ouv;
@@ -1118,12 +1259,12 @@ static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *a
        struct ldb_val *nrf_value = NULL;
        struct ldb_message_element *nrf_el = NULL;
        uint32_t i,j,ni=0;
-       uint64_t seq_num;
        bool found = false;
        time_t t = time(NULL);
        NTTIME now;
        int ret;
 
+       ldb = ldb_module_get_ctx(ar->module);
        ruv = ar->objs->uptodateness_vector;
        ZERO_STRUCT(ouv);
        ouv.version = 2;
@@ -1132,23 +1273,13 @@ static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *a
 
        unix_to_nt_time(&now, t);
 
-       /* 
-        * we use the next sequence number for our own highest_usn
-        * because we will do a modify request and this will increment
-        * our highest_usn
-        */
-       ret = ldb_sequence_number(ar->module->ldb, LDB_SEQ_NEXT, &seq_num);
-       if (ret != LDB_SUCCESS) {
-               return replmd_replicated_request_error(ar, ret);
-       }
-
        /*
         * first create the new replUpToDateVector
         */
-       ouv_value = ldb_msg_find_ldb_val(ar->sub.search_msg, "replUpToDateVector");
+       ouv_value = ldb_msg_find_ldb_val(ar->search_msg, "replUpToDateVector");
        if (ouv_value) {
-               ndr_err = ndr_pull_struct_blob(ouv_value, ar->sub.mem_ctx, 
-                                              lp_iconv_convenience(ldb_get_opaque(ar->module->ldb, "loadparm")), &ouv,
+               ndr_err = ndr_pull_struct_blob(ouv_value, ar,
+                                              lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")), &ouv,
                                               (ndr_pull_flags_fn_t)ndr_pull_replUpToDateVectorBlob);
                if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
                        NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
@@ -1168,7 +1299,7 @@ static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *a
         */
        nuv.ctr.ctr2.count = 1 + ouv.ctr.ctr2.count;
        if (ruv) nuv.ctr.ctr2.count += ruv->count;
-       nuv.ctr.ctr2.cursors = talloc_array(ar->sub.mem_ctx,
+       nuv.ctr.ctr2.cursors = talloc_array(ar,
                                            struct drsuapi_DsReplicaCursor2,
                                            nuv.ctr.ctr2.count);
        if (!nuv.ctr.ctr2.cursors) return replmd_replicated_request_werror(ar, WERR_NOMEM);
@@ -1180,7 +1311,7 @@ static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *a
        }
 
        /* get our invocation_id if we have one already attached to the ldb */
-       our_invocation_id = samdb_ntds_invocation_id(ar->module->ldb);
+       our_invocation_id = samdb_ntds_invocation_id(ldb);
 
        /* merge in the source_dsa vector is available */
        for (i=0; (ruv && i < ruv->count); i++) {
@@ -1269,12 +1400,12 @@ static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *a
        /*
         * create the change ldb_message
         */
-       msg = ldb_msg_new(ar->sub.mem_ctx);
+       msg = ldb_msg_new(ar);
        if (!msg) return replmd_replicated_request_werror(ar, WERR_NOMEM);
-       msg->dn = ar->sub.search_msg->dn;
+       msg->dn = ar->search_msg->dn;
 
        ndr_err = ndr_push_struct_blob(&nuv_value, msg, 
-                                      lp_iconv_convenience(ldb_get_opaque(ar->module->ldb, "loadparm")), 
+                                      lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")), 
                                       &nuv,
                                       (ndr_push_flags_fn_t)ndr_push_replUpToDateVectorBlob);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
@@ -1304,15 +1435,15 @@ static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *a
         * first see if we already have a repsFrom value for the current source dsa
         * if so we'll later replace this value
         */
-       orf_el = ldb_msg_find_element(ar->sub.search_msg, "repsFrom");
+       orf_el = ldb_msg_find_element(ar->search_msg, "repsFrom");
        if (orf_el) {
                for (i=0; i < orf_el->num_values; i++) {
                        struct repsFromToBlob *trf;
 
-                       trf = talloc(ar->sub.mem_ctx, struct repsFromToBlob);
+                       trf = talloc(ar, struct repsFromToBlob);
                        if (!trf) return replmd_replicated_request_werror(ar, WERR_NOMEM);
 
-                       ndr_err = ndr_pull_struct_blob(&orf_el->values[i], trf, lp_iconv_convenience(ldb_get_opaque(ar->module->ldb, "loadparm")), trf,
+                       ndr_err = ndr_pull_struct_blob(&orf_el->values[i], trf, lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")), trf,
                                                       (ndr_pull_flags_fn_t)ndr_pull_repsFromToBlob);
                        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
                                NTSTATUS nt_status = ndr_map_error2ntstatus(ndr_err);
@@ -1363,7 +1494,7 @@ static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *a
 
        /* we now fill the value which is already attached to ldb_message */
        ndr_err = ndr_push_struct_blob(nrf_value, msg, 
-                                      lp_iconv_convenience(ldb_get_opaque(ar->module->ldb, "loadparm")),
+                                      lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")),
                                       &nrf,
                                       (ndr_push_flags_fn_t)ndr_push_repsFromToBlob);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
@@ -1377,143 +1508,137 @@ static int replmd_replicated_uptodate_modify(struct replmd_replicated_request *a
         */
        nrf_el->flags = LDB_FLAG_MOD_REPLACE;
 
+       if (DEBUGLVL(4)) {
+               char *s = ldb_ldif_message_string(ldb, ar, LDB_CHANGETYPE_MODIFY, msg);
+               DEBUG(4, ("DRS replication uptodate modify message:\n%s\n", s));
+               talloc_free(s);
+       }
+
        /* prepare the ldb_modify() request */
-       ret = ldb_build_mod_req(&ar->sub.change_req,
-                               ar->module->ldb,
-                               ar->sub.mem_ctx,
+       ret = ldb_build_mod_req(&change_req,
+                               ldb,
+                               ar,
                                msg,
                                ar->controls,
                                ar,
-                               replmd_replicated_uptodate_modify_callback);
+                               replmd_replicated_uptodate_modify_callback,
+                               ar->req);
        if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
 
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       return ldb_next_request(ar->module, ar->sub.change_req);
-#else
-       ret = ldb_next_request(ar->module, ar->sub.change_req);
-       if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
-
-       ar->sub.change_ret = ldb_wait(ar->sub.search_req->handle, LDB_WAIT_ALL);
-       if (ar->sub.change_ret != LDB_SUCCESS) {
-               return replmd_replicated_request_error(ar, ar->sub.change_ret);
-       }
-
-       talloc_free(ar->sub.mem_ctx);
-       ZERO_STRUCT(ar->sub);
-
-       return replmd_replicated_request_done(ar);
-#endif
+       return ldb_next_request(ar->module, change_req);
 }
 
-static int replmd_replicated_uptodate_search_callback(struct ldb_context *ldb,
-                                                     void *private_data,
+static int replmd_replicated_uptodate_search_callback(struct ldb_request *req,
                                                      struct ldb_reply *ares)
 {
-       struct replmd_replicated_request *ar = talloc_get_type(private_data,
+       struct replmd_replicated_request *ar = talloc_get_type(req->context,
                                               struct replmd_replicated_request);
-       bool is_done = false;
+       int ret;
+
+       if (!ares) {
+               return ldb_module_done(ar->req, NULL, NULL,
+                                       LDB_ERR_OPERATIONS_ERROR);
+       }
+       if (ares->error != LDB_SUCCESS &&
+           ares->error != LDB_ERR_NO_SUCH_OBJECT) {
+               return ldb_module_done(ar->req, ares->controls,
+                                       ares->response, ares->error);
+       }
 
        switch (ares->type) {
        case LDB_REPLY_ENTRY:
-               ar->sub.search_msg = talloc_steal(ar->sub.mem_ctx, ares->message);
+               ar->search_msg = talloc_steal(ar, ares->message);
                break;
+
        case LDB_REPLY_REFERRAL:
                /* we ignore referrals */
                break;
-       case LDB_REPLY_EXTENDED:
-       case LDB_REPLY_DONE:
-               is_done = true;
-       }
 
-       talloc_free(ares);
-
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       if (is_done) {
-               ar->sub.search_ret = ldb_wait(ar->sub.search_req->handle, LDB_WAIT_ALL);
-               if (ar->sub.search_ret != LDB_SUCCESS) {
-                       return replmd_replicated_request_error(ar, ar->sub.search_ret);
+       case LDB_REPLY_DONE:
+               if (ar->search_msg == NULL) {
+                       ret = replmd_replicated_request_werror(ar, WERR_DS_DRA_INTERNAL_ERROR);
+               } else {
+                       ret = replmd_replicated_uptodate_modify(ar);
                }
-               if (!ar->sub.search_msg) {
-                       return replmd_replicated_request_werror(ar, WERR_DS_DRA_INTERNAL_ERROR);
+               if (ret != LDB_SUCCESS) {
+                       return ldb_module_done(ar->req, NULL, NULL, ret);
                }
-
-               return replmd_replicated_uptodate_modify(ar);
        }
-#endif
+
+       talloc_free(ares);
        return LDB_SUCCESS;
 }
 
-static int replmd_replicated_uptodate_search(struct replmd_replicated_request *ar)
+
+static int replmd_replicated_uptodate_vector(struct replmd_replicated_request *ar)
 {
+       struct ldb_context *ldb;
        int ret;
        static const char *attrs[] = {
                "replUpToDateVector",
                "repsFrom",
                NULL
        };
+       struct ldb_request *search_req;
+
+       ldb = ldb_module_get_ctx(ar->module);
+       ar->search_msg = NULL;
 
-       ret = ldb_build_search_req(&ar->sub.search_req,
-                                  ar->module->ldb,
-                                  ar->sub.mem_ctx,
+       ret = ldb_build_search_req(&search_req,
+                                  ldb,
+                                  ar,
                                   ar->objs->partition_dn,
                                   LDB_SCOPE_BASE,
                                   "(objectClass=*)",
                                   attrs,
                                   NULL,
                                   ar,
-                                  replmd_replicated_uptodate_search_callback);
-       if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
-
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       return ldb_next_request(ar->module, ar->sub.search_req);
-#else
-       ret = ldb_next_request(ar->module, ar->sub.search_req);
+                                  replmd_replicated_uptodate_search_callback,
+                                  ar->req);
        if (ret != LDB_SUCCESS) return replmd_replicated_request_error(ar, ret);
 
-       ar->sub.search_ret = ldb_wait(ar->sub.search_req->handle, LDB_WAIT_ALL);
-       if (ar->sub.search_ret != LDB_SUCCESS) {
-               return replmd_replicated_request_error(ar, ar->sub.search_ret);
-       }
-       if (!ar->sub.search_msg) {
-               return replmd_replicated_request_werror(ar, WERR_DS_DRA_INTERNAL_ERROR);
-       }
-
-       return replmd_replicated_uptodate_modify(ar);
-#endif
+       return ldb_next_request(ar->module, search_req);
 }
 
-static int replmd_replicated_uptodate_vector(struct replmd_replicated_request *ar)
-{
-       ar->sub.mem_ctx = talloc_new(ar);
-       if (!ar->sub.mem_ctx) return replmd_replicated_request_werror(ar, WERR_NOMEM);
 
-       return replmd_replicated_uptodate_search(ar);
-}
 
 static int replmd_extended_replicated_objects(struct ldb_module *module, struct ldb_request *req)
 {
+       struct ldb_context *ldb;
        struct dsdb_extended_replicated_objects *objs;
        struct replmd_replicated_request *ar;
        struct ldb_control **ctrls;
-       int ret;
+       int ret, i;
+       struct dsdb_control_current_partition *partition_ctrl;
+       struct replmd_private *replmd_private = 
+               talloc_get_type(ldb_module_get_private(module), struct replmd_private);
 
-       ldb_debug(module->ldb, LDB_DEBUG_TRACE, "replmd_extended_replicated_objects\n");
+       ldb = ldb_module_get_ctx(module);
+
+       ldb_debug(ldb, LDB_DEBUG_TRACE, "replmd_extended_replicated_objects\n");
 
        objs = talloc_get_type(req->op.extended.data, struct dsdb_extended_replicated_objects);
        if (!objs) {
-               ldb_debug(module->ldb, LDB_DEBUG_FATAL, "replmd_extended_replicated_objects: invalid extended data\n");
+               ldb_debug(ldb, LDB_DEBUG_FATAL, "replmd_extended_replicated_objects: invalid extended data\n");
                return LDB_ERR_PROTOCOL_ERROR;
        }
 
        if (objs->version != DSDB_EXTENDED_REPLICATED_OBJECTS_VERSION) {
-               ldb_debug(module->ldb, LDB_DEBUG_FATAL, "replmd_extended_replicated_objects: extended data invalid version [%u != %u]\n",
+               ldb_debug(ldb, LDB_DEBUG_FATAL, "replmd_extended_replicated_objects: extended data invalid version [%u != %u]\n",
                          objs->version, DSDB_EXTENDED_REPLICATED_OBJECTS_VERSION);
                return LDB_ERR_PROTOCOL_ERROR;
        }
 
-       ar = replmd_replicated_init_handle(module, req, objs);
-       if (!ar) {
+       ar = replmd_ctx_init(module, req);
+       if (!ar)
                return LDB_ERR_OPERATIONS_ERROR;
+
+       ar->objs = objs;
+       ar->schema = dsdb_get_schema(ldb);
+       if (!ar->schema) {
+               ldb_debug_set(ldb, LDB_DEBUG_FATAL, "replmd_ctx_init: no loaded schema found\n");
+               talloc_free(ar);
+               return LDB_ERR_CONSTRAINT_VIOLATION;
        }
 
        ctrls = req->controls;
@@ -1529,81 +1654,301 @@ static int replmd_extended_replicated_objects(struct ldb_module *module, struct
                return ret;
        }
 
+       /*
+         add the DSDB_CONTROL_CURRENT_PARTITION_OID control. This
+         tells the partition module which partition this request is
+         directed at. That is important as the partition roots appear
+         twice in the directory, once as mount points in the top
+         level store, and once as the roots of each partition. The
+         replication code wants to operate on the root of the
+         partitions, not the top level mount points
+        */
+       partition_ctrl = talloc(req, struct dsdb_control_current_partition);
+       if (partition_ctrl == NULL) {
+               if (!partition_ctrl) return replmd_replicated_request_werror(ar, WERR_NOMEM);
+       }
+       partition_ctrl->version = DSDB_CONTROL_CURRENT_PARTITION_VERSION;
+       partition_ctrl->dn = objs->partition_dn;
+
+       ret = ldb_request_add_control(req, DSDB_CONTROL_CURRENT_PARTITION_OID, false, partition_ctrl);
+       if (ret != LDB_SUCCESS) {
+               return ret;
+       }
+
        ar->controls = req->controls;
        req->controls = ctrls;
 
-#ifdef REPLMD_FULL_ASYNC /* TODO: activate this code when ldb support full async code */ 
-       return replmd_replicated_apply_next(ar);
-#else
-       while (ar->index_current < ar->objs->num_objects &&
-              req->handle->state != LDB_ASYNC_DONE) { 
-               replmd_replicated_apply_next(ar);
-       }
+       DEBUG(4,("linked_attributes_count=%u\n", objs->linked_attributes_count));
 
-       if (req->handle->state != LDB_ASYNC_DONE) {
-               replmd_replicated_uptodate_vector(ar);
+       /* save away the linked attributes for the end of the
+          transaction */
+       for (i=0; i<ar->objs->linked_attributes_count; i++) {
+               struct la_entry *la_entry;
+
+               if (replmd_private == NULL) {
+                       DEBUG(0,(__location__ ": repl_meta_data not called from within a transaction\n"));
+                       return LDB_ERR_OPERATIONS_ERROR;
+               }
+
+               la_entry = talloc(replmd_private, struct la_entry);
+               if (la_entry == NULL) {
+                       ldb_oom(ldb);
+                       return LDB_ERR_OPERATIONS_ERROR;
+               }
+               la_entry->la = talloc(la_entry, struct drsuapi_DsReplicaLinkedAttribute);
+               if (la_entry->la == NULL) {
+                       ldb_oom(ldb);
+                       return LDB_ERR_OPERATIONS_ERROR;
+               }
+               *la_entry->la = ar->objs->linked_attributes[i];
+
+               /* we need to steal the non-scalars so they stay
+                  around until the end of the transaction */
+               talloc_steal(la_entry->la, la_entry->la->identifier);
+               talloc_steal(la_entry->la, la_entry->la->value.blob);
+
+               DLIST_ADD(replmd_private->la_list, la_entry);
        }
 
-       return LDB_SUCCESS;
-#endif
+       return replmd_replicated_apply_next(ar);
 }
 
-static int replmd_extended(struct ldb_module *module, struct ldb_request *req)
-{
-       if (strcmp(req->op.extended.oid, DSDB_EXTENDED_REPLICATED_OBJECTS_OID) == 0) {
-               return replmd_extended_replicated_objects(module, req);
+/*
+  process one linked attribute structure
+ */
+static int replmd_process_linked_attribute(struct ldb_module *module,
+                                          struct la_entry *la_entry)
+{                                         
+       struct drsuapi_DsReplicaLinkedAttribute *la = la_entry->la;
+       struct ldb_context *ldb = ldb_module_get_ctx(module);
+       struct drsuapi_DsReplicaObjectIdentifier3 target;
+       struct ldb_message *msg;
+       struct ldb_message_element *ret_el;
+       TALLOC_CTX *tmp_ctx = talloc_new(la_entry);
+       enum ndr_err_code ndr_err;
+       char *target_dn;
+       struct ldb_request *mod_req;
+       int ret;
+       const struct dsdb_attribute *attr;
+
+/*
+linked_attributes[0]:                                                     
+     &objs->linked_attributes[i]: struct drsuapi_DsReplicaLinkedAttribute 
+        identifier               : *                                      
+            identifier: struct drsuapi_DsReplicaObjectIdentifier          
+                __ndr_size               : 0x0000003a (58)                
+                __ndr_size_sid           : 0x00000000 (0)                 
+                guid                     : 8e95b6a9-13dd-4158-89db-3220a5be5cc7
+                sid                      : S-0-0                               
+                __ndr_size_dn            : 0x00000000 (0)                      
+                dn                       : ''                                  
+        attid                    : DRSUAPI_ATTRIBUTE_member (0x1F)             
+        value: struct drsuapi_DsAttributeValue                                 
+            __ndr_size               : 0x0000007e (126)                        
+            blob                     : *                                       
+                blob                     : DATA_BLOB length=126                
+        flags                    : 0x00000001 (1)                              
+               1: DRSUAPI_DS_LINKED_ATTRIBUTE_FLAG_ACTIVE                      
+        originating_add_time     : Wed Sep  2 22:20:01 2009 EST                
+        meta_data: struct drsuapi_DsReplicaMetaData                            
+            version                  : 0x00000015 (21)                         
+            originating_change_time  : Wed Sep  2 23:39:07 2009 EST            
+            originating_invocation_id: 794640f3-18cf-40ee-a211-a93992b67a64    
+            originating_usn          : 0x000000000001e19c (123292)             
+     &target: struct drsuapi_DsReplicaObjectIdentifier3                        
+        __ndr_size               : 0x0000007e (126)                            
+        __ndr_size_sid           : 0x0000001c (28)                             
+        guid                     : 7639e594-db75-4086-b0d4-67890ae46031        
+        sid                      : S-1-5-21-2848215498-2472035911-1947525656-19924
+        __ndr_size_dn            : 0x00000022 (34)                                
+        dn                       : 'CN=UOne,OU=TestOU,DC=vsofs8,DC=com'           
+ */
+       if (DEBUGLVL(4)) {
+               NDR_PRINT_DEBUG(drsuapi_DsReplicaLinkedAttribute, la); 
+       }
+       
+       /* decode the target of the link */
+       ndr_err = ndr_pull_struct_blob(la->value.blob, 
+                                      tmp_ctx, lp_iconv_convenience(ldb_get_opaque(ldb, "loadparm")), 
+                                      &target,
+                                      (ndr_pull_flags_fn_t)ndr_pull_drsuapi_DsReplicaObjectIdentifier3);
+       if (ndr_err != NDR_ERR_SUCCESS) {
+               DEBUG(0,("Unable to decode linked_attribute target\n"));
+               dump_data(4, la->value.blob->data, la->value.blob->length);                     
+               talloc_free(tmp_ctx);
+               return LDB_ERR_OPERATIONS_ERROR;
+       }
+       if (DEBUGLVL(4)) {
+               NDR_PRINT_DEBUG(drsuapi_DsReplicaObjectIdentifier3, &target);
        }
 
-       return ldb_next_request(module, req);
-}
+       /* construct a modify request for this attribute change */
+       msg = ldb_msg_new(tmp_ctx);
+       if (!msg) {
+               ldb_oom(ldb);
+               talloc_free(tmp_ctx);
+               return LDB_ERR_OPERATIONS_ERROR;
+       }
 
-static int replmd_wait_none(struct ldb_handle *handle) {
-       struct replmd_replicated_request *ar;
-    
-       if (!handle || !handle->private_data) {
+       ret = dsdb_find_dn_by_guid(ldb, tmp_ctx, 
+                                  GUID_string(tmp_ctx, &la->identifier->guid), &msg->dn);
+       if (ret != LDB_SUCCESS) {
+               talloc_free(tmp_ctx);
+               return ret;
+       }
+
+       /* find the attribute being modified */
+       attr = dsdb_attribute_by_attributeID_id(dsdb_get_schema(ldb), la->attid);
+       if (attr == NULL) {
+               DEBUG(0, (__location__ ": Unable to find attributeID 0x%x\n", la->attid));
+               talloc_free(tmp_ctx);
                return LDB_ERR_OPERATIONS_ERROR;
        }
 
-       ar = talloc_get_type(handle->private_data, struct replmd_replicated_request);
-       if (!ar) {
+       if (la->flags & DRSUAPI_DS_LINKED_ATTRIBUTE_FLAG_ACTIVE) {
+               ret = ldb_msg_add_empty(msg, attr->lDAPDisplayName,
+                                       LDB_FLAG_MOD_ADD, &ret_el);
+       } else {
+               ret = ldb_msg_add_empty(msg, attr->lDAPDisplayName,
+                                       LDB_FLAG_MOD_DELETE, &ret_el);
+       }
+       if (ret != LDB_SUCCESS) {
+               talloc_free(tmp_ctx);
+               return ret;
+       }
+       ret_el->values = talloc_array(msg, struct ldb_val, 1);
+       if (!ret_el->values) {
+               ldb_oom(ldb);
+               talloc_free(tmp_ctx);
                return LDB_ERR_OPERATIONS_ERROR;
        }
+       ret_el->num_values = 1;
 
-       /* we do only sync calls */
-       if (handle->state != LDB_ASYNC_DONE) {
+       target_dn = talloc_asprintf(tmp_ctx, "<GUID=%s>;<SID=%s>;%s",
+                                   GUID_string(tmp_ctx, &target.guid),
+                                   dom_sid_string(tmp_ctx, &target.sid),
+                                   target.dn);
+       if (target_dn == NULL) {
+               ldb_oom(ldb);
+               talloc_free(tmp_ctx);
                return LDB_ERR_OPERATIONS_ERROR;
        }
+       ret_el->values[0] = data_blob_string_const(target_dn);
 
-       return handle->status;
+       ret = ldb_build_mod_req(&mod_req, ldb, tmp_ctx,
+                               msg,
+                               NULL,
+                               NULL, 
+                               ldb_op_default_callback,
+                               NULL);
+       if (ret != LDB_SUCCESS) {
+               talloc_free(tmp_ctx);
+               return ret;
+       }
+       talloc_steal(mod_req, msg);
+
+       if (DEBUGLVL(4)) {
+               DEBUG(4,("Applying DRS linked attribute change:\n%s\n",
+                        ldb_ldif_message_string(ldb, tmp_ctx, LDB_CHANGETYPE_MODIFY, msg)));
+       }
+
+       /* Run the new request */
+       ret = ldb_next_request(module, mod_req);
+
+       /* we need to wait for this to finish, as we are being called
+          from the synchronous end_transaction hook of this module */
+       if (ret == LDB_SUCCESS) {
+               ret = ldb_wait(mod_req->handle, LDB_WAIT_ALL);
+       }
+
+       if (ret != LDB_SUCCESS) {
+               ldb_debug(ldb, LDB_DEBUG_WARNING, "Failed to apply linked attribute change '%s' %s\n",
+                         ldb_errstring(ldb),
+                         ldb_ldif_message_string(ldb, tmp_ctx, LDB_CHANGETYPE_MODIFY, msg));
+       }
+       
+       talloc_free(tmp_ctx);
+
+       return ret;     
 }
 
-static int replmd_wait_all(struct ldb_handle *handle) {
+static int replmd_extended(struct ldb_module *module, struct ldb_request *req)
+{
+       if (strcmp(req->op.extended.oid, DSDB_EXTENDED_REPLICATED_OBJECTS_OID) == 0) {
+               return replmd_extended_replicated_objects(module, req);
+       }
 
-       int ret;
+       return ldb_next_request(module, req);
+}
+
+
+/*
+  we hook into the transaction operations to allow us to 
+  perform the linked attribute updates at the end of the whole
+  transaction. This allows a forward linked attribute to be created
+  before the object is created. During a vampire, w2k8 sends us linked
+  attributes before the objects they are part of.
+ */
+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);
+       replmd_private = talloc(module, struct replmd_private);
+       if (replmd_private == NULL) {
+               return LDB_ERR_OPERATIONS_ERROR;
+       }
+       replmd_private->la_list = NULL;
+       ldb_module_set_private(module, replmd_private);
+       return ldb_next_start_trans(module);
+}
 
-       while (handle->state != LDB_ASYNC_DONE) {
-               ret = replmd_wait_none(handle);
+/*
+  on prepare commit we loop over our queued la_context structures and
+  apply each of them  
+ */
+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;
+
+       /* walk the list backwards, to do the first entry first, as we
+        * added the entries with DLIST_ADD() which puts them at the
+        * start of the list */
+       for (la = replmd_private->la_list; la && la->next; la=la->next) ;
+
+       for (; la; la=la->prev) {
+               int ret;
+               ret = replmd_process_linked_attribute(module, la);
                if (ret != LDB_SUCCESS) {
                        return ret;
                }
        }
 
-       return handle->status;
+       talloc_free(replmd_private);
+       ldb_module_set_private(module, NULL);
+       
+       return ldb_next_prepare_commit(module);
 }
 
-static int replmd_wait(struct ldb_handle *handle, enum ldb_wait_type type)
+static int replmd_del_transaction(struct ldb_module *module)
 {
-       if (type == LDB_WAIT_ALL) {
-               return replmd_wait_all(handle);
-       } else {
-               return replmd_wait_none(handle);
-       }
+       struct replmd_private *replmd_private = 
+               talloc_get_type(ldb_module_get_private(module), struct replmd_private);
+       talloc_free(replmd_private);
+       ldb_module_set_private(module, NULL);
+       return ldb_next_del_trans(module);
 }
 
+
 _PUBLIC_ const struct ldb_module_ops ldb_repl_meta_data_module_ops = {
        .name          = "repl_meta_data",
        .add           = replmd_add,
        .modify        = replmd_modify,
        .extended      = replmd_extended,
-       .wait          = replmd_wait
+       .start_transaction = replmd_start_transaction,
+       .prepare_commit    = replmd_prepare_commit,
+       .del_transaction   = replmd_del_transaction,
 };