support for no-op search control (ITS#6598)

contrib/slapd-modules/noopsrch/Makefile

+# $OpenLDAP$
+# This work is part of OpenLDAP Software <http://www.openldap.org/>.
+#
+# Copyright 1998-2010 The OpenLDAP Foundation.
+# Copyright 2004 Howard Chu, Symas Corp. All Rights Reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted only as authorized by the OpenLDAP
+# Public License.
+#
+# A copy of this license is available in the file LICENSE in the
+# top-level directory of the distribution or, alternatively, at
+# <http://www.OpenLDAP.org/license.html>.
+
+LIBTOOL=../../../libtool
+OPT=-DSLAPD_OVER_NOOPSRCH=2 -g -O2
+#LIBTOOL=../../../../ldap-devel/libtool
+#OPT=-DSLAPD_OVER_NOOPSRCH=2 -g -O0
+CC=gcc
+
+LDAP_INC=-I../../../include -I../../../servers/slapd
+#LDAP_INC=-I../../../include -I../../../servers/slapd -I../../../../ldap-devel/include
+INCS=$(LDAP_INC)
+
+LDAP_LIB=-lldap_r -llber
+LIBS=$(LDAP_LIB)
+
+prefix=/usr/local
+exec_prefix=$(prefix)
+ldap_subdir=/openldap
+
+libdir=$(exec_prefix)/lib
+libexecdir=$(exec_prefix)/libexec
+moduledir = $(libexecdir)$(ldap_subdir)
+
+all:	noopsrch.la
+
+
+noopsrch.lo:	noopsrch.c
+	$(LIBTOOL) --mode=compile $(CC) $(OPT) $(DEFS) $(INCS) -c $?
+
+noopsrch.la:	noopsrch.lo
+	$(LIBTOOL) --mode=link $(CC) $(OPT) -version-info 0:0:0 \
+	-rpath $(moduledir) -module -o $@ $? $(LIBS)
+
+clean:
+	rm -f noopsrch.lo noopsrch.la
+
+install: noopsrch.la
+	mkdir -p $(DESTDIR)$(moduledir)
+	$(LIBTOOL) --mode=install cp noopsrch.la $(DESTDIR)$(moduledir)
+

contrib/slapd-modules/noopsrch/noopsrch.c

+/* noopsrch.c - LDAP Control that counts entries a search would return */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2010 The OpenLDAP Foundation.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+/* ACKNOWLEDGEMENTS:
+ * This work was initially developed by Pierangelo Masarati for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+/* define SLAPD_OVER_NOOPSRCH=2 to build as run-time loadable module */
+#ifdef SLAPD_OVER_NOOPSRCH
+
+/*
+ * Control OID
+ */
+#define	LDAP_CONTROL_X_NOOPSRCH		"1.3.6.1.4.1.4203.666.5.18"
+
+#include "slap.h"
+#include "ac/string.h"
+
+#define o_noopsrch			o_ctrlflag[noopsrch_cid]
+#define o_ctrlnoopsrch		o_controls[noopsrch_cid]
+
+static int noopsrch_cid;
+static slap_overinst noopsrch;
+
+static int
+noopsrch_parseCtrl (
+	Operation *op,
+	SlapReply *rs,
+	LDAPControl *ctrl )
+{
+	if ( op->o_noopsrch != SLAP_CONTROL_NONE ) {
+		rs->sr_text = "No-op Search control specified multiple times";
+		return LDAP_PROTOCOL_ERROR;
+	}
+
+	if ( !BER_BVISNULL( &ctrl->ldctl_value ) ) {
+		rs->sr_text = "No-op Search control value is present";
+		return LDAP_PROTOCOL_ERROR;
+	}
+
+	op->o_ctrlnoopsrch = (void *)NULL;
+
+	op->o_noopsrch = ctrl->ldctl_iscritical
+		? SLAP_CONTROL_CRITICAL
+		: SLAP_CONTROL_NONCRITICAL;
+
+	rs->sr_err = LDAP_SUCCESS;
+
+	return rs->sr_err;
+}
+
+int dummy;
+
+typedef struct noopsrch_cb_t {
+	slap_overinst	*nc_on;
+	ber_int_t		nc_nentries;
+	ber_int_t		nc_nsearchref;
+	AttributeName	*nc_save_attrs;
+	int				*nc_pdummy;
+	int				nc_save_slimit;
+} noopsrch_cb_t;
+
+static int
+noopsrch_response( Operation *op, SlapReply *rs )
+{
+	noopsrch_cb_t		*nc = (noopsrch_cb_t *)op->o_callback->sc_private;
+
+	/* if the control is global, limits are not computed yet  */
+	if ( nc->nc_pdummy == &dummy ) {	
+		nc->nc_save_slimit = op->ors_slimit;
+		op->ors_slimit = SLAP_NO_LIMIT;
+		nc->nc_pdummy = NULL;
+	}
+
+	if ( rs->sr_type == REP_SEARCH ) {
+		nc->nc_nentries++;
+#ifdef NOOPSRCH_DEBUG
+		Debug( LDAP_DEBUG_TRACE, "noopsrch_response(REP_SEARCH): nentries=%d\n", nc->nc_nentries, 0, 0 );
+#endif
+		return 0;
+
+	} else if ( rs->sr_type == REP_SEARCHREF ) {
+		nc->nc_nsearchref++;
+		return 0;
+
+	} else if ( rs->sr_type == REP_RESULT ) {
+		BerElementBuffer	berbuf;
+		BerElement			*ber = (BerElement *) &berbuf;
+		struct berval		ctrlval;
+		LDAPControl			*ctrl, *ctrlsp[2];
+		int					rc = rs->sr_err;
+
+		if ( nc->nc_save_slimit >= 0 && nc->nc_nentries >= nc->nc_save_slimit ) {
+			rc = LDAP_SIZELIMIT_EXCEEDED;
+		}
+
+#ifdef NOOPSRCH_DEBUG
+		Debug( LDAP_DEBUG_TRACE, "noopsrch_response(REP_RESULT): err=%d nentries=%d nref=%d\n", rc, nc->nc_nentries, nc->nc_nsearchref );
+#endif
+
+		ber_init2( ber, NULL, LBER_USE_DER );
+
+		ber_printf( ber, "{iii}", rc, nc->nc_nentries, nc->nc_nsearchref );
+		if ( ber_flatten2( ber, &ctrlval, 0 ) == -1 ) {
+			ber_free_buf( ber );
+			if ( op->o_noopsrch == SLAP_CONTROL_CRITICAL ) {
+				return LDAP_CONSTRAINT_VIOLATION;
+			}
+			return SLAP_CB_CONTINUE;
+		}
+
+		ctrl = op->o_tmpcalloc( 1,
+			sizeof( LDAPControl ) + ctrlval.bv_len + 1,
+			op->o_tmpmemctx );
+		ctrl->ldctl_value.bv_val = (char *)&ctrl[ 1 ];
+		ctrl->ldctl_oid = LDAP_CONTROL_X_NOOPSRCH;
+		ctrl->ldctl_iscritical = 0;
+		ctrl->ldctl_value.bv_len = ctrlval.bv_len;
+		AC_MEMCPY( ctrl->ldctl_value.bv_val, ctrlval.bv_val, ctrlval.bv_len );
+		ctrl->ldctl_value.bv_val[ ctrl->ldctl_value.bv_len ] = '\0';
+
+		ber_free_buf( ber );
+
+		ctrlsp[0] = ctrl;
+		ctrlsp[1] = NULL;
+		slap_add_ctrls( op, rs, ctrlsp );
+
+		return SLAP_CB_CONTINUE;
+	}
+}
+
+static int
+noopsrch_cleanup( Operation *op, SlapReply *rs )
+{
+	if ( rs->sr_type == REP_RESULT || rs->sr_err == SLAPD_ABANDON ) {
+		noopsrch_cb_t		*nc = (noopsrch_cb_t *)op->o_callback->sc_private;
+		op->ors_attrs = nc->nc_save_attrs;
+		if ( nc->nc_pdummy == NULL ) {
+			op->ors_slimit = nc->nc_save_slimit;
+		}
+
+		op->o_tmpfree( op->o_callback, op->o_tmpmemctx );
+		op->o_callback = NULL;
+	}
+
+	return SLAP_CB_CONTINUE;
+}
+
+static int
+noopsrch_op_search( Operation *op, SlapReply *rs )
+{
+	if ( op->o_noopsrch != SLAP_CONTROL_NONE ) {
+		slap_callback *sc;
+		noopsrch_cb_t *nc;
+
+		sc = op->o_tmpcalloc( 1, sizeof( slap_callback ) + sizeof( noopsrch_cb_t ), op->o_tmpmemctx );
+
+		nc = (noopsrch_cb_t *)&sc[ 1 ];
+		nc->nc_on = (slap_overinst *)op->o_bd->bd_info;
+		nc->nc_nentries = 0;
+		nc->nc_nsearchref = 0;
+		nc->nc_save_attrs = op->ors_attrs;
+		nc->nc_pdummy = &dummy;
+
+		sc->sc_response = noopsrch_response;
+		sc->sc_cleanup = noopsrch_cleanup;
+		sc->sc_private = (void *)nc;
+
+		op->ors_attrs = slap_anlist_no_attrs;
+
+		sc->sc_next = op->o_callback->sc_next;
+                op->o_callback->sc_next = sc;
+	}
+	
+	return SLAP_CB_CONTINUE;
+}
+
+#if SLAPD_OVER_NOOPSRCH == SLAPD_MOD_DYNAMIC
+static
+#endif /* SLAPD_OVER_NOOPSRCH == SLAPD_MOD_DYNAMIC */
+int
+noopsrch_initialize( void )
+{
+	int rc;
+
+	rc = register_supported_control( LDAP_CONTROL_X_NOOPSRCH,
+		SLAP_CTRL_SEARCH, NULL,
+		noopsrch_parseCtrl, &noopsrch_cid );
+	if ( rc != LDAP_SUCCESS ) {
+		Debug( LDAP_DEBUG_ANY,
+			"noopsrch_initialize: Failed to register control (%d)\n",
+			rc, 0, 0 );
+		return -1;
+	}
+
+	noopsrch.on_bi.bi_type = "noopsrch";
+
+	noopsrch.on_bi.bi_op_search = noopsrch_op_search;
+
+	return overlay_register( &noopsrch );
+}
+
+#if SLAPD_OVER_NOOPSRCH == SLAPD_MOD_DYNAMIC
+int
+init_module( int argc, char *argv[] )
+{
+	return noopsrch_initialize();
+}
+#endif /* SLAPD_OVER_NOOPSRCH == SLAPD_MOD_DYNAMIC */
+
+#endif /* SLAPD_OVER_NOOPSRCH */