s4: ran minimal_includes.pl on source4/rpc_server
[ira/wip.git] / source4 / rpc_server / drsuapi / getncchanges.c
1 /* 
2    Unix SMB/CIFS implementation.
3
4    implement the DRSUpdateRefs call
5
6    Copyright (C) Anatoliy Atanasov 2009
7    Copyright (C) Andrew Tridgell 2009
8    
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 3 of the License, or
12    (at your option) any later version.
13    
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18    
19    You should have received a copy of the GNU General Public License
20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
21 */
22
23 #include "includes.h"
24 #include "rpc_server/dcerpc_server.h"
25 #include "dsdb/samdb/samdb.h"
26 #include "param/param.h"
27 #include "librpc/gen_ndr/ndr_drsblobs.h"
28 #include "rpc_server/drsuapi/dcesrv_drsuapi.h"
29 #include "rpc_server/dcerpc_server_proto.h"
30 #include "../libcli/drsuapi/drsuapi.h"
31 #include "libcli/security/security.h"
32
33 /* 
34   drsuapi_DsGetNCChanges for one object
35 */
36 static WERROR get_nc_changes_build_object(struct drsuapi_DsReplicaObjectListItemEx *obj,
37                                           struct ldb_message *msg,
38                                           struct ldb_context *sam_ctx,
39                                           struct ldb_dn *ncRoot_dn,
40                                           struct dsdb_schema *schema,
41                                           DATA_BLOB *session_key,
42                                           uint64_t highest_usn,
43                                           uint32_t replica_flags)
44 {
45         const struct ldb_val *md_value;
46         int i, n;
47         struct ldb_dn *obj_dn;
48         struct replPropertyMetaDataBlob md;
49         struct dom_sid *sid;
50         uint32_t rid = 0;
51         enum ndr_err_code ndr_err;
52         uint32_t *attids;
53         const char *rdn;
54         const struct dsdb_attribute *rdn_sa;
55
56         if (ldb_dn_compare(ncRoot_dn, msg->dn) == 0) {
57                 obj->is_nc_prefix = true;
58                 obj->parent_object_guid = NULL;
59         } else {
60                 struct ldb_dn *parent_dn;
61                 uint32_t instance_type;
62
63                 instance_type = ldb_msg_find_attr_as_uint(msg, "instanceType", 0);
64                 if (instance_type & INSTANCE_TYPE_IS_NC_HEAD) {
65                         struct ldb_result *res;
66                         int ret;
67                         const char *dnstr = ldb_dn_get_linearized(msg->dn);
68                         msg->dn = ldb_dn_new(msg, sam_ctx, dnstr);
69                         /* we need to re-search the msg, to avoid the
70                          * broken dual message problems with our
71                          * partitions implementation */
72                         DEBUG(6,(__location__ ": Re-fetching subref %s\n", 
73                                  ldb_dn_get_linearized(msg->dn)));
74                         ret = drsuapi_search_with_extended_dn(sam_ctx, msg, &res,
75                                                               msg->dn, LDB_SCOPE_BASE, NULL,
76                                                               NULL, NULL);
77                         if (ret != LDB_SUCCESS || res->count < 1) {
78                                 DEBUG(0,(__location__ ": Failed to reload subref head %s in %s\n",
79                                          ldb_dn_get_linearized(msg->dn), ldb_dn_get_linearized(ncRoot_dn)));
80                                 return WERR_DS_DRA_INTERNAL_ERROR;
81                         }
82                         msg = res->msgs[0];
83                 }
84
85                 parent_dn = ldb_dn_copy(msg, msg->dn);
86                 obj->is_nc_prefix = false;
87                 obj->parent_object_guid = talloc(obj, struct GUID);
88                 if (parent_dn == NULL) {
89                         return WERR_DS_DRA_INTERNAL_ERROR;
90                 }
91                 if (ldb_dn_remove_child_components(parent_dn, 1) != true) {
92                         DEBUG(0,(__location__ ": Unable to remove DN component\n"));
93                         return WERR_DS_DRA_INTERNAL_ERROR;
94                 }
95                 if (dsdb_find_guid_by_dn(sam_ctx, parent_dn, obj->parent_object_guid) != LDB_SUCCESS) {
96                         DEBUG(0,(__location__ ": Unable to find parent DN %s %s\n", 
97                                  ldb_dn_get_linearized(msg->dn), ldb_dn_get_linearized(parent_dn)));
98                 }
99                 talloc_free(parent_dn);
100         }
101         obj->next_object = NULL;
102         
103         md_value = ldb_msg_find_ldb_val(msg, "replPropertyMetaData");
104         if (!md_value) {
105                 /* nothing to send */
106                 return WERR_OK;
107         }
108
109         ndr_err = ndr_pull_struct_blob(md_value, obj,
110                                        lp_iconv_convenience(ldb_get_opaque(sam_ctx, "loadparm")), &md,
111                                        (ndr_pull_flags_fn_t)ndr_pull_replPropertyMetaDataBlob);
112         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
113                 return WERR_DS_DRA_INTERNAL_ERROR;
114         }
115         
116         if (md.version != 1) {
117                 return WERR_DS_DRA_INTERNAL_ERROR;
118         }
119
120         rdn = ldb_dn_get_rdn_name(msg->dn);
121         if (rdn == NULL) {
122                 DEBUG(0,(__location__ ": No rDN for %s\n", ldb_dn_get_linearized(msg->dn)));
123                 return WERR_DS_DRA_INTERNAL_ERROR;
124         }
125
126         rdn_sa = dsdb_attribute_by_lDAPDisplayName(schema, rdn);
127         if (rdn_sa == NULL) {
128                 DEBUG(0,(__location__ ": Can't find dsds_attribute for rDN %s in %s\n", 
129                          rdn, ldb_dn_get_linearized(msg->dn)));
130                 return WERR_DS_DRA_INTERNAL_ERROR;
131         }
132
133         obj->meta_data_ctr = talloc(obj, struct drsuapi_DsReplicaMetaDataCtr);
134         attids = talloc_array(obj, uint32_t, md.ctr.ctr1.count);
135         
136         obj->meta_data_ctr->meta_data = talloc_array(obj, struct drsuapi_DsReplicaMetaData, md.ctr.ctr1.count);
137         for (n=i=0; i<md.ctr.ctr1.count; i++) {
138                 /* if the attribute has not changed, and it is not the
139                    instanceType then don't include it */
140                 if (md.ctr.ctr1.array[i].local_usn < highest_usn &&
141                     md.ctr.ctr1.array[i].attid != DRSUAPI_ATTRIBUTE_instanceType) continue;
142
143                 /* don't include the rDN */
144                 if (md.ctr.ctr1.array[i].attid == rdn_sa->attributeID_id) continue;
145
146                 obj->meta_data_ctr->meta_data[n].originating_change_time = md.ctr.ctr1.array[i].originating_change_time;
147                 obj->meta_data_ctr->meta_data[n].version = md.ctr.ctr1.array[i].version;
148                 obj->meta_data_ctr->meta_data[n].originating_invocation_id = md.ctr.ctr1.array[i].originating_invocation_id;
149                 obj->meta_data_ctr->meta_data[n].originating_usn = md.ctr.ctr1.array[i].originating_usn;
150                 attids[n] = md.ctr.ctr1.array[i].attid;
151                 n++;
152         }
153
154         /*
155           note that if n==0 we still need to send the change, as it
156           could be a rename, which changes the uSNChanged, but not any
157           of the replicated attributes
158          */
159
160         obj->meta_data_ctr->count = n;
161
162         obj->object.identifier = talloc(obj, struct drsuapi_DsReplicaObjectIdentifier);
163         obj_dn = ldb_msg_find_attr_as_dn(sam_ctx, obj, msg, "distinguishedName");
164         obj->object.identifier->dn = ldb_dn_get_linearized(obj_dn);
165         obj->object.identifier->guid = samdb_result_guid(msg, "objectGUID");
166         sid = samdb_result_dom_sid(obj, msg, "objectSid");
167         if (sid) {
168                 dom_sid_split_rid(NULL, sid, NULL, &rid);
169                 obj->object.identifier->sid = *sid;
170         } else {
171                 ZERO_STRUCT(obj->object.identifier->sid);
172         }
173
174         obj->object.flags = DRSUAPI_DS_REPLICA_OBJECT_FROM_MASTER;
175         obj->object.attribute_ctr.num_attributes = obj->meta_data_ctr->count;
176         obj->object.attribute_ctr.attributes = talloc_array(obj, struct drsuapi_DsReplicaAttribute,
177                                                             obj->object.attribute_ctr.num_attributes);
178
179         /*
180          * Note that the meta_data array and the attributes array must
181          * be the same size and in the same order
182          */
183         for (i=0; i<obj->object.attribute_ctr.num_attributes; i++) {
184                 struct ldb_message_element *el;
185                 WERROR werr;
186                 const struct dsdb_attribute *sa;
187         
188                 sa = dsdb_attribute_by_attributeID_id(schema, attids[i]);
189                 if (!sa) {
190                         DEBUG(0,("Unable to find attributeID %u in schema\n", attids[i]));
191                         return WERR_DS_DRA_INTERNAL_ERROR;
192                 }
193
194                 el = ldb_msg_find_element(msg, sa->lDAPDisplayName);
195                 if (el == NULL) {
196                         DEBUG(0,("No element '%s' for attributeID %u in message\n", 
197                                  sa->lDAPDisplayName, attids[i]));
198                         ZERO_STRUCT(obj->object.attribute_ctr.attributes[i]);
199                         obj->object.attribute_ctr.attributes[i].attid = attids[i];
200                 } else {
201                         werr = dsdb_attribute_ldb_to_drsuapi(sam_ctx, schema, el, obj,
202                                                              &obj->object.attribute_ctr.attributes[i]);
203                         if (!W_ERROR_IS_OK(werr)) {
204                                 DEBUG(0,("Unable to convert %s to DRS object - %s\n", 
205                                          sa->lDAPDisplayName, win_errstr(werr)));
206                                 return werr;
207                         }
208                         /* if DRSUAPI_DRS_SPECIAL_SECRET_PROCESSING is set
209                          * check if attribute is secret and send a null value
210                          */
211                         if (replica_flags & DRSUAPI_DRS_SPECIAL_SECRET_PROCESSING) {
212                                 drsuapi_process_secret_attribute(&obj->object.attribute_ctr.attributes[i],
213                                                                  &obj->meta_data_ctr->meta_data[i]);
214                         }
215                         /* some attributes needs to be encrypted
216                            before being sent */
217                         werr = drsuapi_encrypt_attribute(obj, session_key, rid, 
218                                                          &obj->object.attribute_ctr.attributes[i]);
219                         if (!W_ERROR_IS_OK(werr)) {
220                                 DEBUG(0,("Unable to encrypt %s in DRS object - %s\n", 
221                                          sa->lDAPDisplayName, win_errstr(werr)));
222                                 return werr;
223                         }
224                 }
225         }
226
227         return WERR_OK;
228 }
229
230 /*
231   load replUpToDateVector from a DN
232  */
233 static WERROR load_udv(struct ldb_context *sam_ctx, TALLOC_CTX *mem_ctx,
234                        struct ldb_dn *dn, struct replUpToDateVectorBlob *ouv)
235 {
236         const char *attrs[] = { "replUpToDateVector", NULL };
237         struct ldb_result *res = NULL;
238         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
239         struct ldb_message_element *el;
240         enum ndr_err_code ndr_err;
241
242         ZERO_STRUCTP(ouv);
243
244         if (ldb_search(sam_ctx, tmp_ctx, &res, dn, LDB_SCOPE_BASE, attrs, NULL) != LDB_SUCCESS ||
245             res->count < 1) {
246                 DEBUG(0,("load_udv: failed to read partition object\n"));
247                 talloc_free(tmp_ctx);
248                 return WERR_DS_DRA_INTERNAL_ERROR;
249         }
250
251         el = ldb_msg_find_element(res->msgs[0], "replUpToDateVector");
252         if (el == NULL || el->num_values < 1) {
253                 talloc_free(tmp_ctx);
254                 ouv->version = 2;
255                 return WERR_OK;
256         }
257
258         ndr_err = ndr_pull_struct_blob(&el->values[0], 
259                                        mem_ctx, lp_iconv_convenience(ldb_get_opaque(sam_ctx, "loadparm")),
260                                        ouv, 
261                                        (ndr_pull_flags_fn_t)ndr_pull_replUpToDateVectorBlob);
262         talloc_free(tmp_ctx);
263         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
264                 DEBUG(0,(__location__ ": Failed to parse replUpToDateVector for %s\n",
265                          ldb_dn_get_linearized(dn)));
266                 return WERR_DS_DRA_INTERNAL_ERROR;
267         }
268         
269         return WERR_OK;
270         
271 }
272
273 /*
274   fill in the cursors return based on the replUpToDateVector for the ncRoot_dn
275  */
276 static WERROR get_nc_changes_udv(struct ldb_context *sam_ctx,
277                                  struct ldb_dn *ncRoot_dn,
278                                  struct drsuapi_DsReplicaCursor2CtrEx *udv)
279 {
280         WERROR werr;
281         struct drsuapi_DsReplicaCursor2 *tmp_cursor;
282         uint64_t highest_commited_usn;
283         NTTIME now;
284         time_t t = time(NULL);
285         int ret;
286         struct replUpToDateVectorBlob ouv;
287
288         werr = load_udv(sam_ctx, udv, ncRoot_dn, &ouv);
289         if (!W_ERROR_IS_OK(werr)) {
290                 return werr;
291         }
292         
293         ret = ldb_sequence_number(sam_ctx, LDB_SEQ_HIGHEST_SEQ, &highest_commited_usn);
294         if (ret != LDB_SUCCESS) {
295                 return WERR_DS_DRA_INTERNAL_ERROR;
296         }
297
298         tmp_cursor = talloc(udv, struct drsuapi_DsReplicaCursor2);
299         tmp_cursor->source_dsa_invocation_id = *(samdb_ntds_invocation_id(sam_ctx));
300         tmp_cursor->highest_usn = highest_commited_usn;
301         unix_to_nt_time(&now, t);
302         tmp_cursor->last_sync_success = now;
303
304         udv->count = ouv.ctr.ctr2.count + 1;
305         udv->cursors = talloc_steal(udv, ouv.ctr.ctr2.cursors);
306         udv->cursors = talloc_realloc(udv, udv->cursors, struct drsuapi_DsReplicaCursor2, udv->count);
307         if (!udv->cursors) {
308                 return WERR_DS_DRA_INTERNAL_ERROR;
309         }
310         udv->cursors[udv->count - 1] = *tmp_cursor;
311         
312         qsort(udv->cursors, udv->count,
313               sizeof(struct drsuapi_DsReplicaCursor2),
314               (comparison_fn_t)drsuapi_DsReplicaCursor2_compare);
315
316         return WERR_OK;
317 }
318
319 /* state of a partially completed getncchanges call */
320 struct drsuapi_getncchanges_state {
321         struct ldb_result *site_res;
322         uint32_t num_sent;
323         struct ldb_dn *ncRoot_dn;
324         uint32_t min_usn;
325 };
326
327 /* 
328   drsuapi_DsGetNCChanges
329
330   see MS-DRSR 4.1.10.5.2 for basic logic of this function
331 */
332 WERROR dcesrv_drsuapi_DsGetNCChanges(struct dcesrv_call_state *dce_call, TALLOC_CTX *mem_ctx,
333                                      struct drsuapi_DsGetNCChanges *r)
334 {
335         struct drsuapi_DsReplicaObjectIdentifier *ncRoot;
336         int ret;
337         int i;
338         struct dsdb_schema *schema;
339         struct drsuapi_DsReplicaOIDMapping_Ctr *ctr;
340         struct drsuapi_DsReplicaObjectListItemEx **currentObject;
341         NTSTATUS status;
342         DATA_BLOB session_key;
343         const char *attrs[] = { "*", "distinguishedName", NULL };
344         WERROR werr;
345         struct dcesrv_handle *h;
346         struct drsuapi_bind_state *b_state;     
347         struct drsuapi_getncchanges_state *getnc_state;
348         struct drsuapi_DsGetNCChangesRequest8 *req8;
349         uint32_t options;
350
351         DCESRV_PULL_HANDLE_WERR(h, r->in.bind_handle, DRSUAPI_BIND_HANDLE);
352         b_state = h->data;
353
354         *r->out.level_out = 6;
355         /* TODO: linked attributes*/
356         r->out.ctr->ctr6.linked_attributes_count = 0;
357         r->out.ctr->ctr6.linked_attributes = NULL;
358
359         r->out.ctr->ctr6.object_count = 0;
360         r->out.ctr->ctr6.nc_object_count = 0;
361         r->out.ctr->ctr6.more_data = false;
362         r->out.ctr->ctr6.uptodateness_vector = NULL;
363
364         /* a RODC doesn't allow for any replication */
365         if (samdb_rodc(ldb_get_opaque(b_state->sam_ctx, "loadparm"))) {
366                 DEBUG(0,(__location__ ": DsGetNCChanges attempt on RODC\n"));
367                 return WERR_DS_DRA_SOURCE_DISABLED;
368         }
369
370         /* Check request revision. 
371            TODO: Adding mappings to req8 from the other levels
372          */
373         if (r->in.level != 8) {
374                 DEBUG(0,(__location__ ": Request for DsGetNCChanges with unsupported level %u\n",
375                          r->in.level));
376                 return WERR_REVISION_MISMATCH;
377         }
378
379         req8 = &r->in.req->req8;
380
381         /* Perform access checks. */
382         ncRoot = req8->naming_context;
383         if (ncRoot == NULL) {
384                 DEBUG(0,(__location__ ": Request for DsGetNCChanges with no NC\n"));
385                 return WERR_DS_DRA_INVALID_PARAMETER;
386         }
387
388         if (samdb_ntds_options(b_state->sam_ctx, &options) != LDB_SUCCESS) {
389                 return WERR_DS_DRA_INTERNAL_ERROR;
390         }
391         
392         if ((options & DS_NTDSDSA_OPT_DISABLE_OUTBOUND_REPL) &&
393             !(req8->replica_flags & DRSUAPI_DRS_SYNC_FORCED)) {
394                 return WERR_DS_DRA_SOURCE_DISABLED;
395         }
396
397
398         if (req8->replica_flags & DRSUAPI_DS_REPLICA_NEIGHBOUR_FULL_SYNC_PACKET) {
399                 /* Ignore the _in_ uptpdateness vector*/
400                 req8->uptodateness_vector = NULL;
401         } 
402
403         werr = drs_security_level_check(dce_call, "DsGetNCChanges");
404         if (!W_ERROR_IS_OK(werr)) {
405                 return werr;
406         }
407
408         getnc_state = b_state->getncchanges_state;
409         if (getnc_state == NULL) {
410                 getnc_state = talloc_zero(b_state, struct drsuapi_getncchanges_state);
411                 if (getnc_state == NULL) {
412                         return WERR_NOMEM;
413                 }
414                 b_state->getncchanges_state = getnc_state;
415         }
416
417         /* we need the session key for encrypting password attributes */
418         status = dcesrv_inherited_session_key(dce_call->conn, &session_key);
419         if (!NT_STATUS_IS_OK(status)) {
420                 DEBUG(0,(__location__ ": Failed to get session key\n"));
421                 return WERR_DS_DRA_INTERNAL_ERROR;              
422         }
423
424         /* we don't yet support extended operations */
425         if (req8->extended_op != DRSUAPI_EXOP_NONE) {
426                 DEBUG(0,(__location__ ": Request for DsGetNCChanges extended op 0x%x\n",
427                          (unsigned)req8->extended_op));
428                 return WERR_DS_DRA_NOT_SUPPORTED;
429         }
430
431         /* 
432            TODO: MS-DRSR section 4.1.10.1.1
433            Work out if this is the start of a new cycle */
434
435         if (getnc_state->site_res == NULL) {
436                 char* search_filter;
437                 enum ldb_scope scope = LDB_SCOPE_SUBTREE;
438
439                 getnc_state->min_usn = req8->highwatermark.highest_usn;
440
441                 /* Construct response. */
442                 search_filter = talloc_asprintf(mem_ctx,
443                                                 "(uSNChanged>=%llu)",
444                                                 (unsigned long long)(getnc_state->min_usn+1));
445         
446                 if (req8->replica_flags & DRSUAPI_DS_REPLICA_NEIGHBOUR_CRITICAL_ONLY) {
447                         search_filter = talloc_asprintf(mem_ctx,
448                                                         "(&%s(isCriticalSystemObject=TRUE))",
449                                                         search_filter);
450                 }
451                 
452                 getnc_state->ncRoot_dn = ldb_dn_new(getnc_state, b_state->sam_ctx, ncRoot->dn);
453                 if (req8->replica_flags & DRSUAPI_DS_REPLICA_NEIGHBOUR_ASYNC_REP) {
454                         scope = LDB_SCOPE_BASE;
455                 }
456                 
457                 DEBUG(6,(__location__ ": getncchanges on %s using filter %s\n",
458                          ldb_dn_get_linearized(getnc_state->ncRoot_dn), search_filter));
459                 ret = drsuapi_search_with_extended_dn(b_state->sam_ctx, getnc_state, &getnc_state->site_res,
460                                                       getnc_state->ncRoot_dn, scope, attrs,
461                                                       "uSNChanged",
462                                                       search_filter);
463                 if (ret != LDB_SUCCESS) {
464                         return WERR_DS_DRA_INTERNAL_ERROR;
465                 }
466         } else {
467                 /* check that this request is for the same NC as the previous one */
468                 struct ldb_dn *dn;
469                 dn = ldb_dn_new(getnc_state, b_state->sam_ctx, ncRoot->dn);
470                 if (!dn) {
471                         return WERR_NOMEM;
472                 }
473                 if (ldb_dn_compare(dn, getnc_state->ncRoot_dn) != 0) {
474                         DEBUG(0,(__location__ ": DsGetNCChanges 2nd replication on different DN %s %s\n",
475                                  ldb_dn_get_linearized(dn),
476                                  ldb_dn_get_linearized(getnc_state->ncRoot_dn)));
477                         return WERR_DS_DRA_BAD_NC;
478                 }
479         }
480
481         /* Prefix mapping */
482         schema = dsdb_get_schema(b_state->sam_ctx);
483         if (!schema) {
484                 DEBUG(0,("No schema in sam_ctx\n"));
485                 return WERR_DS_DRA_INTERNAL_ERROR;
486         }
487
488         r->out.ctr->ctr6.naming_context = talloc(mem_ctx, struct drsuapi_DsReplicaObjectIdentifier);
489         *r->out.ctr->ctr6.naming_context = *ncRoot;
490
491         if (dsdb_find_guid_by_dn(b_state->sam_ctx, getnc_state->ncRoot_dn, 
492                                  &r->out.ctr->ctr6.naming_context->guid) != LDB_SUCCESS) {
493                 DEBUG(0,(__location__ ": Failed to find GUID of ncRoot_dn %s\n",
494                          ldb_dn_get_linearized(getnc_state->ncRoot_dn)));
495                 return WERR_DS_DRA_INTERNAL_ERROR;
496         }
497
498         /* find the SID if there is one */
499         dsdb_find_sid_by_dn(b_state->sam_ctx, getnc_state->ncRoot_dn, &r->out.ctr->ctr6.naming_context->sid);
500
501         dsdb_get_oid_mappings_drsuapi(schema, true, mem_ctx, &ctr);
502         r->out.ctr->ctr6.mapping_ctr = *ctr;
503
504         r->out.ctr->ctr6.source_dsa_guid = *(samdb_ntds_objectGUID(b_state->sam_ctx));
505         r->out.ctr->ctr6.source_dsa_invocation_id = *(samdb_ntds_invocation_id(b_state->sam_ctx));
506
507         r->out.ctr->ctr6.old_highwatermark = req8->highwatermark;
508         r->out.ctr->ctr6.new_highwatermark = req8->highwatermark;
509
510         r->out.ctr->ctr6.first_object = NULL;
511         currentObject = &r->out.ctr->ctr6.first_object;
512
513         for(i=getnc_state->num_sent; 
514             i<getnc_state->site_res->count && 
515                     (r->out.ctr->ctr6.object_count < req8->max_object_count);
516             i++) {
517                 int uSN;
518                 struct drsuapi_DsReplicaObjectListItemEx *obj;
519                 obj = talloc_zero(mem_ctx, struct drsuapi_DsReplicaObjectListItemEx);
520
521                 uSN = ldb_msg_find_attr_as_int(getnc_state->site_res->msgs[i], "uSNChanged", -1);
522                 if (uSN > r->out.ctr->ctr6.new_highwatermark.tmp_highest_usn) {
523                         r->out.ctr->ctr6.new_highwatermark.tmp_highest_usn = uSN;
524                 }
525
526                 werr = get_nc_changes_build_object(obj, getnc_state->site_res->msgs[i], 
527                                                    b_state->sam_ctx, getnc_state->ncRoot_dn, 
528                                                    schema, &session_key, getnc_state->min_usn,
529                                                    req8->replica_flags);
530                 if (!W_ERROR_IS_OK(werr)) {
531                         return werr;
532                 }
533
534                 if (obj->meta_data_ctr == NULL) {
535                         DEBUG(0,(__location__ ": getncchanges skipping send of object %s\n",
536                                  ldb_dn_get_linearized(getnc_state->site_res->msgs[i]->dn)));
537                         /* no attributes to send */
538                         talloc_free(obj);
539                         continue;
540                 }
541
542                 r->out.ctr->ctr6.object_count++;
543                 
544                 *currentObject = obj;
545                 currentObject = &obj->next_object;
546         }
547
548         getnc_state->num_sent += r->out.ctr->ctr6.object_count;
549
550         r->out.ctr->ctr6.nc_object_count = getnc_state->site_res->count;
551
552         /* the client can us to call UpdateRefs on its behalf to
553            re-establish monitoring of the NC */
554         if ((req8->replica_flags & DRSUAPI_DRS_ADD_REF) && 
555             !GUID_all_zero(&req8->destination_dsa_guid)) {
556                 struct drsuapi_DsReplicaUpdateRefsRequest1 ureq;
557                 ureq.naming_context = ncRoot;
558                 ureq.dest_dsa_dns_name = talloc_asprintf(mem_ctx, "%s._msdcs.%s",
559                                                          GUID_string(mem_ctx, &req8->destination_dsa_guid),
560                                                          lp_realm(dce_call->conn->dce_ctx->lp_ctx));
561                 if (!ureq.dest_dsa_dns_name) {
562                         return WERR_NOMEM;
563                 }
564                 ureq.dest_dsa_guid = req8->destination_dsa_guid;
565                 ureq.options = DRSUAPI_DS_REPLICA_UPDATE_ADD_REFERENCE |
566                         DRSUAPI_DS_REPLICA_UPDATE_ASYNCHRONOUS_OPERATION |
567                         DRSUAPI_DS_REPLICA_UPDATE_GETCHG_CHECK;
568                 werr = drsuapi_UpdateRefs(b_state, mem_ctx, &ureq);
569                 if (!W_ERROR_IS_OK(werr)) {
570                         DEBUG(0,(__location__ ": Failed UpdateRefs in DsGetNCChanges - %s\n",
571                                  win_errstr(werr)));
572                 }
573         }
574
575         if (i < getnc_state->site_res->count) {
576                 r->out.ctr->ctr6.more_data = true;
577         } else {
578                 r->out.ctr->ctr6.uptodateness_vector = talloc(mem_ctx, struct drsuapi_DsReplicaCursor2CtrEx);
579                 r->out.ctr->ctr6.uptodateness_vector->version = 2;
580                 r->out.ctr->ctr6.uptodateness_vector->reserved1 = 0;
581                 r->out.ctr->ctr6.uptodateness_vector->reserved2 = 0;
582
583                 r->out.ctr->ctr6.new_highwatermark.highest_usn = r->out.ctr->ctr6.new_highwatermark.tmp_highest_usn;
584
585                 werr = get_nc_changes_udv(b_state->sam_ctx, getnc_state->ncRoot_dn, 
586                                           r->out.ctr->ctr6.uptodateness_vector);
587                 if (!W_ERROR_IS_OK(werr)) {
588                         return werr;
589                 }
590
591                 talloc_free(getnc_state);
592                 b_state->getncchanges_state = NULL;
593         }
594
595         DEBUG(2,("DsGetNCChanges with uSNChanged >= %llu flags 0x%08x on %s gave %u objects\n", 
596                  (unsigned long long)(req8->highwatermark.highest_usn+1),
597                  req8->replica_flags,
598                  ncRoot->dn, r->out.ctr->ctr6.object_count));
599
600         return WERR_OK;
601 }