ITS#7702 fix results with aliases

Aliases pointing within the original search scope could cause
the same entry to be returned multiple times. Check for subtree
scope and duplicate scopes.

servers/slapd/back-mdb/dn2id.c

@@ -556,7 +556,8 @@ mdb_id2name(
 	MDB_cursor **cursp,
 	ID id,
 	struct berval *name,
-	struct berval *nname )
+	struct berval *nname,
+	ID *iscopes )
 {
 	struct mdb_info *mdb = (struct mdb_info *) op->o_bd->be_private;
 	MDB_dbi dbi = mdb->mi_dn2id;
@@ -589,6 +590,11 @@ mdb_id2name(
 		ptr = data.mv_data;
 		ptr += data.mv_size - sizeof(ID);
 		memcpy( &id, ptr, sizeof(ID) );
+		if ( iscopes ) {
+			rc = mdb_idl_search( iscopes, id );
+			if ( iscopes[rc] == id )
+				return MDB_KEYEXIST;
+		}
 		d = data.mv_data;
 		nrlen = (d->nrdnlen[0] << 8) | d->nrdnlen[1];
 		rlen = data.mv_size - sizeof(diskNode) - nrlen;

servers/slapd/back-mdb/proto-mdb.h

@@ -123,7 +123,8 @@ int mdb_id2name(
 	MDB_cursor **cursp,
 	ID eid,
 	struct berval *name,
-	struct berval *nname);
+	struct berval *nname,
+	ID *iscopes );
 
 int mdb_idscope(
 	Operation *op,

servers/slapd/back-mdb/search.c

@@ -722,12 +722,9 @@ dn2entry_retry:
 		if (scopes[0].mid > 1) {
 			cursor = 1;
 			for (cscope = 1; cscope <= scopes[0].mid; cscope++) {
-				/* Ignore the original base */
-				if (scopes[cscope].mid == base->e_id)
-					continue;
 				iscopes[cursor++] = scopes[cscope].mid;
 			}
-			iscopes[0] = scopes[0].mid - 1;
+			iscopes[0] = scopes[0].mid;
 		} else {
 			iscopes[0] = 0;
 		}
@@ -740,7 +737,7 @@ dn2entry_retry:
 			id = NOID;
 		else
 			id = isc.id;
-		cscope = 0;
+		cscope = 1;	/* skip original base */
 	} else {
 		id = mdb_idl_first( candidates, &cursor );
 		wwctx.mcd = NULL;
@@ -952,7 +949,7 @@ notfound:
 				pdn = base->e_name;
 				pndn = base->e_nname;
 			} else {
-				mdb_id2name( op, ltid, &isc.mc, scopes[isc.nscope].mid, &pdn, &pndn );
+				mdb_id2name( op, ltid, &isc.mc, scopes[isc.nscope].mid, &pdn, &pndn, NULL );
 			}
 			e->e_name.bv_len = pdn.bv_len;
 			e->e_nname.bv_len = pndn.bv_len;
@@ -1129,7 +1126,13 @@ loop_continue:
 						mdb_entry_return( op, base );
 					rs->sr_err = mdb_id2entry(op, mci, isc.id, &base);
 					if ( !rs->sr_err ) {
-						mdb_id2name( op, ltid, &isc.mc, isc.id, &base->e_name, &base->e_nname );
+						rc = mdb_id2name( op, ltid, &isc.mc, isc.id, &base->e_name, &base->e_nname,
+							op->ors_scope == LDAP_SCOPE_SUBTREE ? iscopes : NULL );
+						if ( rc == MDB_KEYEXIST ) {
+							mdb_entry_return( op, base );
+							base = NULL;
+							continue;
+						}
 						isc.numrdns = 0;
 						if (isc.oscope == LDAP_SCOPE_ONELEVEL)
 							isc.oscope = LDAP_SCOPE_BASE;

servers/slapd/back-mdb/tools.c

@@ -380,7 +380,7 @@ mdb_tool_entry_get_int( BackendDB *be, ID id, Entry **ep )
 	op.o_tmpmemctx = NULL;
 	op.o_tmpmfuncs = &ch_mfuncs;
 	if ( slapMode & SLAP_TOOL_READONLY ) {
-		rc = mdb_id2name( &op, mdb_tool_txn, &idcursor, id, &dn, &ndn );
+		rc = mdb_id2name( &op, mdb_tool_txn, &idcursor, id, &dn, &ndn, NULL );
 		if ( rc  ) {
 			rc = LDAP_OTHER;
 			if ( e ) {