VILLASnode/include/villas/kernel/tc.hpp

/** Setup interface queuing desciplines for network emulation
 *
 * We use the firewall mark to apply individual netem qdiscs
 * per node. Every node uses an own BSD socket.
 * By using so SO_MARK socket option (see socket(7))
 * we can classify traffic originating from a node seperately.
 *
 * @file
 * @author Steffen Vogel <post@steffenvogel.de>
 * @copyright 2014-2022, Institute for Automation of Complex Power Systems, EONERC
 * @license Apache 2.0
 *********************************************************************************/

#pragma once

#include <cstdint>

#include <netlink/route/qdisc.h>
#include <netlink/route/classifier.h>

#include <jansson.h>

namespace villas {
namespace kernel {

/* Forward declarations */
class Interface;

namespace tc {

typedef uint32_t tc_hdl_t;

/** Remove all queuing disciplines and filters.
 *
 * @param i The interface
 * @retval 0 Success. Everything went well.
 * @retval <0 Error. Something went wrong.
 */
int reset(Interface *i);

/** Create a priority (prio) queueing discipline.
 *
 * @param i[in] The interface
 * @param qd[in,out] The libnl3 object of the new prio qdisc.
 * @param handle[in] The handle for the new qdisc
 * @param parent[in] Make this qdisc a child of this class
 * @param bands[in] The number of classes for this new qdisc
 * @retval 0 Success. Everything went well.
 * @retval <0 Error. Something went wrong.
 */
int prio(Interface *i, struct rtnl_qdisc **qd, tc_hdl_t handle, tc_hdl_t, int bands);

/** Add a new filter based on the netfilter mark.
 *
 * @param i The interface to which this classifier is applied to.
 * @param cls[in,out] The libnl3 object of the new prio qdisc.
 * @param flowid The destination class for matched traffic
 * @param mark The netfilter firewall mark (sometime called 'fwmark')
 * @retval 0 Success. Everything went well.
 * @retval <0 Error. Something went wrong.
*/
int mark(Interface *i, struct rtnl_cls **cls, tc_hdl_t flowid, uint32_t mark);

} // namespace tc
} // namespace kernel
} // namespace villas