getncchanges: calculate getnc_state->min_usn calculation based on the uptodateness...

This should improve initial replication of a fresh destination dsa with
a zero highwatermark.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=12398

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

diff --git a/source4/rpc_server/drsuapi/getncchanges.c b/source4/rpc_server/drsuapi/getncchanges.c
index 62b6e3a4fdb788be135d3068dc51372b14904908..45f00ea6479be3ed04d886a04f54a632cc37a761 100644 (file)
--- a/source4/rpc_server/drsuapi/getncchanges.c
+++ b/source4/rpc_server/drsuapi/getncchanges.c
@@ -2063,10 +2063,33 @@ allowed:
        if (getnc_state->guids == NULL) {
                const char *extra_filter;
                struct ldb_result *search_res = NULL;
+               static const struct drsuapi_DsReplicaCursorCtrEx empty_udv;
+               const struct drsuapi_DsReplicaCursorCtrEx *udv = NULL;
 
                extra_filter = lpcfg_parm_string(dce_call->conn->dce_ctx->lp_ctx, NULL, "drs", "object filter");
 
+               if (req10->uptodateness_vector != NULL) {
+                       udv = req10->uptodateness_vector;
+               } else {
+                       udv = &empty_udv;
+               }
+
                getnc_state->min_usn = req10->highwatermark.highest_usn;
+               for (i = 0; i < udv->count; i++) {
+                       bool match;
+                       const struct drsuapi_DsReplicaCursor *cur =
+                               &udv->cursors[i];
+
+                       match = GUID_equal(&invocation_id,
+                                          &cur->source_dsa_invocation_id);
+                       if (!match) {
+                               continue;
+                       }
+                       if (cur->highest_usn > getnc_state->min_usn) {
+                               getnc_state->min_usn = cur->highest_usn;
+                       }
+                       break;
+               }
                getnc_state->max_usn = getnc_state->min_usn;
 
                getnc_state->final_udv = talloc_zero(getnc_state,