s4-repl: added request for RID allocation in drepl task

The drepl task now checks to see if our rIDAllocationPool is
exhausted, and if it is then we queue a extended operation
DsGetNCChanges call to ask the RID Manager to give us a new allocation
pool.

Pair-Programmed-With: Andrew Bartlett <abartlet@samba.org>

7 files changed, 276 insertions, 13 deletions

diff --git a/source4/dsdb/config.mk b/source4/dsdb/config.mk
index 35a0c84903..3226c08ec0 100644
--- a/source4/dsdb/config.mk
+++ b/source4/dsdb/config.mk
@@ -64,7 +64,8 @@ DREPL_SRV_OBJ_FILES = $(addprefix $(dsdbsrcdir)/repl/, \
 		drepl_partitions.o \
 		drepl_out_pull.o \
 		drepl_out_helpers.o \
-		drepl_notify.o)
+		drepl_notify.o \
+		drepl_ridalloc.o)
 
 $(eval $(call proto_header_template,$(dsdbsrcdir)/repl/drepl_service_proto.h,$(DREPL_SRV_OBJ_FILES:.o=.c)))
 
diff --git a/source4/dsdb/repl/drepl_out_helpers.c b/source4/dsdb/repl/drepl_out_helpers.c
index 722db4f8ee..1225edecc7 100644
--- a/source4/dsdb/repl/drepl_out_helpers.c
+++ b/source4/dsdb/repl/drepl_out_helpers.c
@@ -289,7 +289,7 @@ static void dreplsrv_op_pull_source_get_changes_send(struct dreplsrv_op_pull_sou
 		r->in.req->req8.replica_flags		= rf1->replica_flags;
 		r->in.req->req8.max_object_count	= 133;
 		r->in.req->req8.max_ndr_size		= 1336811;
-		r->in.req->req8.extended_op		= DRSUAPI_EXOP_NONE;
+		r->in.req->req8.extended_op		= st->op->extended_op;
 		r->in.req->req8.fsmo_info		= 0;
 		r->in.req->req8.partial_attribute_set	= NULL;
 		r->in.req->req8.partial_attribute_set_ex= NULL;
@@ -305,7 +305,7 @@ static void dreplsrv_op_pull_source_get_changes_send(struct dreplsrv_op_pull_sou
 		r->in.req->req5.replica_flags		= rf1->replica_flags;
 		r->in.req->req5.max_object_count	= 133;
 		r->in.req->req5.max_ndr_size		= 1336770;
-		r->in.req->req5.extended_op		= DRSUAPI_EXOP_NONE;
+		r->in.req->req5.extended_op		= st->op->extended_op;
 		r->in.req->req5.fsmo_info		= 0;
 	}
 
diff --git a/source4/dsdb/repl/drepl_out_pull.c b/source4/dsdb/repl/drepl_out_pull.c
index 2793eec8b4..ceec61848d 100644
--- a/source4/dsdb/repl/drepl_out_pull.c
+++ b/source4/dsdb/repl/drepl_out_pull.c
@@ -33,21 +33,21 @@
 #include "librpc/gen_ndr/ndr_drsblobs.h"
 #include "libcli/composite/composite.h"
 
-static WERROR dreplsrv_schedule_partition_pull_source(struct dreplsrv_service *s,
-						      struct dreplsrv_partition *p,
-						      struct dreplsrv_partition_source_dsa *source,
-						      TALLOC_CTX *mem_ctx)
+WERROR dreplsrv_schedule_partition_pull_source(struct dreplsrv_service *s,
+					       struct dreplsrv_partition_source_dsa *source,
+					       enum drsuapi_DsExtendedOperation extended_op)
 {
 	struct dreplsrv_out_operation *op;
 
-	op = talloc_zero(mem_ctx, struct dreplsrv_out_operation);
+	op = talloc_zero(s, struct dreplsrv_out_operation);
 	W_ERROR_HAVE_NO_MEMORY(op);
 
 	op->service	= s;
 	op->source_dsa	= source;
+	op->extended_op = extended_op;
 
 	DLIST_ADD_END(s->ops.pending, op, struct dreplsrv_out_operation *);
-	talloc_steal(s, op);
+
 	return WERR_OK;
 }
 
@@ -59,7 +59,7 @@ static WERROR dreplsrv_schedule_partition_pull(struct dreplsrv_service *s,
 	struct dreplsrv_partition_source_dsa *cur;
 
 	for (cur = p->sources; cur; cur = cur->next) {
-		status = dreplsrv_schedule_partition_pull_source(s, p, cur, mem_ctx);
+		status = dreplsrv_schedule_partition_pull_source(s, cur, DRSUAPI_EXOP_NONE);
 		W_ERROR_NOT_OK_RETURN(status);
 	}
 
diff --git a/source4/dsdb/repl/drepl_partitions.c b/source4/dsdb/repl/drepl_partitions.c
index 5b8227e7de..f5c8a701a9 100644
--- a/source4/dsdb/repl/drepl_partitions.c
+++ b/source4/dsdb/repl/drepl_partitions.c
@@ -88,9 +88,9 @@ WERROR dreplsrv_load_partitions(struct dreplsrv_service *s)
 	return WERR_OK;
 }
 
-static WERROR dreplsrv_out_connection_attach(struct dreplsrv_service *s,
-					     const struct repsFromTo1 *rft,
-					     struct dreplsrv_out_connection **_conn)
+WERROR dreplsrv_out_connection_attach(struct dreplsrv_service *s,
+				      const struct repsFromTo1 *rft,
+				      struct dreplsrv_out_connection **_conn)
 {
 	struct dreplsrv_out_connection *cur, *conn = NULL;
 	const char *hostname;
diff --git a/source4/dsdb/repl/drepl_periodic.c b/source4/dsdb/repl/drepl_periodic.c
index 61d5598207..d2fbe45586 100644
--- a/source4/dsdb/repl/drepl_periodic.c
+++ b/source4/dsdb/repl/drepl_periodic.c
@@ -109,6 +109,8 @@ static void dreplsrv_periodic_run(struct dreplsrv_service *service)
 	/* the KCC might have changed repsFrom */
 	dreplsrv_refresh_partitions(service);
 
+	dreplsrv_ridalloc_check_rid_pool(service);
+
 	dreplsrv_run_pending_ops(service);
 	dreplsrv_notify_run_ops(service);
 }
diff --git a/source4/dsdb/repl/drepl_ridalloc.c b/source4/dsdb/repl/drepl_ridalloc.c
new file mode 100644
index 0000000000..34f75862da
--- /dev/null
+++ b/source4/dsdb/repl/drepl_ridalloc.c
@@ -0,0 +1,254 @@
+/*
+   Unix SMB/CIFS mplementation.
+
+   DSDB replication service - RID allocation code
+
+   Copyright (C) Andrew Tridgell 2010
+   Copyright (C) Andrew Bartlett 2010
+
+   based on drepl_notify.c
+
+   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 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 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 "dsdb/samdb/samdb.h"
+#include "smbd/service.h"
+#include "dsdb/repl/drepl_service.h"
+#include "param/param.h"
+
+
+/*
+  create the RID manager source dsa structure
+ */
+static WERROR drepl_create_rid_manager_source_dsa(struct dreplsrv_service *service,
+						  struct ldb_dn *rid_manager_dn, struct ldb_dn *fsmo_role_dn)
+{
+	struct dreplsrv_partition_source_dsa *sdsa;
+	struct ldb_context *ldb = service->samdb;
+	int ret;
+	WERROR werr;
+
+	sdsa = talloc_zero(service, struct dreplsrv_partition_source_dsa);
+	W_ERROR_HAVE_NO_MEMORY(sdsa);
+
+	sdsa->partition = talloc_zero(sdsa, struct dreplsrv_partition);
+	if (!sdsa->partition) {
+		talloc_free(sdsa);
+		return WERR_NOMEM;
+	}
+
+	sdsa->partition->dn = samdb_base_dn(ldb);
+	sdsa->partition->nc.dn = ldb_dn_alloc_linearized(sdsa->partition, rid_manager_dn);
+	ret = dsdb_find_guid_by_dn(ldb, rid_manager_dn, &sdsa->partition->nc.guid);
+	if (ret != LDB_SUCCESS) {
+		DEBUG(0,(__location__ ": Failed to find GUID for %s\n",
+			 ldb_dn_get_linearized(rid_manager_dn)));
+		talloc_free(sdsa);
+		return WERR_DS_DRA_INTERNAL_ERROR;
+	}
+
+	sdsa->repsFrom1 = &sdsa->_repsFromBlob.ctr.ctr1;
+	ret = dsdb_find_guid_attr_by_dn(ldb, fsmo_role_dn, "objectGUID", &sdsa->repsFrom1->source_dsa_obj_guid);
+	if (ret != LDB_SUCCESS) {
+		DEBUG(0,(__location__ ": Failed to find objectGUID for %s\n",
+			 ldb_dn_get_linearized(fsmo_role_dn)));
+		talloc_free(sdsa);
+		return WERR_DS_DRA_INTERNAL_ERROR;
+	}
+
+	sdsa->repsFrom1->other_info = talloc_zero(sdsa, struct repsFromTo1OtherInfo);
+	if (!sdsa->repsFrom1->other_info) {
+		talloc_free(sdsa);
+		return WERR_NOMEM;
+	}
+
+	sdsa->repsFrom1->other_info->dns_name =
+		talloc_asprintf(sdsa->repsFrom1->other_info, "%s._msdcs.%s",
+				GUID_string(sdsa->repsFrom1->other_info, &sdsa->repsFrom1->source_dsa_obj_guid),
+				lp_dnsdomain(service->task->lp_ctx));
+	if (!sdsa->repsFrom1->other_info->dns_name) {
+		talloc_free(sdsa);
+		return WERR_NOMEM;
+	}
+
+
+	werr = dreplsrv_out_connection_attach(service, sdsa->repsFrom1, &sdsa->conn);
+	if (!W_ERROR_IS_OK(werr)) {
+		DEBUG(0,(__location__ ": Failed to attach to RID manager connection\n"));
+		talloc_free(sdsa);
+		return werr;
+	}
+
+	service->ridalloc.rid_manager_source_dsa = sdsa;
+	return WERR_OK;
+}
+
+
+/*
+  schedule a getncchanges request to the RID Manager to ask for a new
+  set of RIDs using DRSUAPI_EXOP_FSMO_RID_ALLOC
+ */
+static WERROR drepl_request_new_rid_pool(struct dreplsrv_service *service,
+					 struct ldb_dn *rid_manager_dn, struct ldb_dn *fsmo_role_dn)
+{
+	WERROR werr;
+
+	if (service->ridalloc.rid_manager_source_dsa == NULL) {
+		/* we need to establish a connection to the RID
+		   Manager */
+		werr = drepl_create_rid_manager_source_dsa(service, rid_manager_dn, fsmo_role_dn);
+		W_ERROR_NOT_OK_RETURN(werr);
+	}
+
+	werr = dreplsrv_schedule_partition_pull_source(service, service->ridalloc.rid_manager_source_dsa,
+						       DRSUAPI_EXOP_FSMO_RID_ALLOC);
+	return werr;
+}
+
+
+/*
+  see if we are on the last pool we have
+ */
+static int drepl_ridalloc_pool_exhausted(struct ldb_context *ldb, bool *exhausted)
+{
+	struct ldb_dn *server_dn, *machine_dn, *rid_set_dn;
+	TALLOC_CTX *tmp_ctx = talloc_new(ldb);
+	uint64_t alloc_pool, prev_alloc_pool;
+	const char *attrs[] = { "rIDPreviousAllocationPool", "rIDAllocationPool", NULL };
+	int ret;
+	struct ldb_result *res;
+
+	server_dn = ldb_dn_get_parent(tmp_ctx, samdb_ntds_settings_dn(ldb));
+	if (!server_dn) {
+		talloc_free(tmp_ctx);
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+
+	ret = samdb_reference_dn(ldb, tmp_ctx, server_dn, "serverReference", &machine_dn);
+	if (ret != LDB_SUCCESS) {
+		DEBUG(0,(__location__ ": Failed to find serverReference in %s - %s",
+			 ldb_dn_get_linearized(server_dn), ldb_errstring(ldb)));
+		talloc_free(tmp_ctx);
+		return ret;
+	}
+
+	ret = samdb_reference_dn(ldb, tmp_ctx, machine_dn, "rIDSetReferences", &rid_set_dn);
+	if (ret == LDB_ERR_NO_SUCH_ATTRIBUTE) {
+		*exhausted = true;
+		talloc_free(tmp_ctx);
+		return LDB_SUCCESS;
+	}
+	if (ret != LDB_SUCCESS) {
+		DEBUG(0,(__location__ ": Failed to find rIDSetReferences in %s - %s",
+			 ldb_dn_get_linearized(machine_dn), ldb_errstring(ldb)));
+		talloc_free(tmp_ctx);
+		return ret;
+	}
+
+	ret = ldb_search(ldb, tmp_ctx, &res, rid_set_dn, LDB_SCOPE_BASE, attrs, NULL);
+	if (ret != LDB_SUCCESS) {
+		DEBUG(0,(__location__ ": Failed to load RID Set attrs from %s - %s",
+			 ldb_dn_get_linearized(rid_set_dn), ldb_errstring(ldb)));
+		talloc_free(tmp_ctx);
+		return ret;
+	}
+
+	alloc_pool = ldb_msg_find_attr_as_uint64(res->msgs[0], "rIDAllocationPool", 0);
+	prev_alloc_pool = ldb_msg_find_attr_as_uint64(res->msgs[0], "rIDPreviousAllocationPool", 0);
+
+	if (alloc_pool != prev_alloc_pool) {
+		*exhausted = false;
+	} else {
+		*exhausted = true;
+	}
+
+	talloc_free(tmp_ctx);
+	return LDB_SUCCESS;
+}
+
+
+/*
+  see if we are low on RIDs in the RID Set rIDAllocationPool. If we
+  are, then schedule a replication call with DRSUAPI_EXOP_FSMO_RID_ALLOC
+  to the RID Manager
+ */
+WERROR dreplsrv_ridalloc_check_rid_pool(struct dreplsrv_service *service)
+{
+	struct ldb_dn *rid_manager_dn, *fsmo_role_dn;
+	TALLOC_CTX *tmp_ctx = talloc_new(service);
+	struct ldb_context *ldb = service->samdb;
+	bool exhausted;
+	WERROR werr;
+	int ret;
+
+	/*
+	  steps:
+	    - find who the RID Manager is
+	    - if we are the RID Manager then nothing to do
+	    - find our RID Set object
+	    - load rIDAllocationPool and rIDPreviousAllocationPool
+	    - if rIDAllocationPool != rIDPreviousAllocationPool then
+	      nothing to do
+	    - schedule a getncchanges with DRSUAPI_EXOP_FSMO_RID_ALLOC
+	      to the RID Manager
+	 */
+
+	/* work out who is the RID Manager */
+	ret = samdb_rid_manager_dn(ldb, tmp_ctx, &rid_manager_dn);
+	if (ret != LDB_SUCCESS) {
+		DEBUG(0, (__location__ ": Failed to find RID Manager object - %s", ldb_errstring(ldb)));
+		talloc_free(tmp_ctx);
+		return WERR_DS_DRA_INTERNAL_ERROR;
+	}
+
+	/* find the DN of the RID Manager */
+	ret = samdb_reference_dn(ldb, tmp_ctx, rid_manager_dn, "fSMORoleOwner", &fsmo_role_dn);
+	if (ret != LDB_SUCCESS) {
+		DEBUG(0,(__location__ ": Failed to find fSMORoleOwner in RID Manager object - %s",
+			 ldb_errstring(ldb)));
+		talloc_free(tmp_ctx);
+		return WERR_DS_DRA_INTERNAL_ERROR;
+	}
+
+	if (ldb_dn_compare(samdb_ntds_settings_dn(ldb), fsmo_role_dn) == 0) {
+		/* we are the RID Manager - no need to do a
+		   DRSUAPI_EXOP_FSMO_RID_ALLOC */
+		talloc_free(tmp_ctx);
+		return WERR_OK;
+	}
+
+	ret = drepl_ridalloc_pool_exhausted(ldb, &exhausted);
+	if (ret != LDB_SUCCESS) {
+		talloc_free(tmp_ctx);
+		return WERR_DS_DRA_INTERNAL_ERROR;
+	}
+
+	if (!exhausted) {
+		/* if we're not exhausted we don't need the exop call */
+		talloc_free(tmp_ctx);
+
+		/* we don't need to keep an open connection to the RID
+		   Manager */
+		talloc_free(service->ridalloc.rid_manager_source_dsa);
+		service->ridalloc.rid_manager_source_dsa = NULL;
+
+		return WERR_OK;
+	}
+
+	werr = drepl_request_new_rid_pool(service, rid_manager_dn, fsmo_role_dn);
+	talloc_free(tmp_ctx);
+	return werr;
+}
diff --git a/source4/dsdb/repl/drepl_service.h b/source4/dsdb/repl/drepl_service.h
index 0f9684fa78..eb3cd045f9 100644
--- a/source4/dsdb/repl/drepl_service.h
+++ b/source4/dsdb/repl/drepl_service.h
@@ -108,6 +108,8 @@ struct dreplsrv_out_operation {
 	struct dreplsrv_partition_source_dsa *source_dsa;
 
 	struct composite_context *creq;
+
+	enum drsuapi_DsExtendedOperation extended_op;
 };
 
 struct dreplsrv_notify_operation {
@@ -204,6 +206,10 @@ struct dreplsrv_service {
 		/* an active notify operation */
 		struct dreplsrv_notify_operation *n_current;
 	} ops;
+
+	struct {
+		struct dreplsrv_partition_source_dsa *rid_manager_source_dsa;
+	} ridalloc;
 };
 
 #include "dsdb/repl/drepl_out_helpers.h"