path: root/sys/altq/altq_cdnr.c

/*	$OpenBSD: altq_cdnr.c,v 1.7 2002/12/16 17:27:20 henning Exp $	*/
/*	$KAME: altq_cdnr.c,v 1.8 2000/12/14 08:12:45 thorpej Exp $	*/

/*
 * Copyright (C) 1999-2000
 *	Sony Computer Science Laboratories Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY SONY CSL AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL SONY CSL OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/queue.h>

#include <net/if.h>
#include <net/if_types.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#ifdef INET6
#include <netinet/ip6.h>
#endif

#include <altq/altq.h>
#include <altq/altq_cdnr.h>

/*
 * diffserv traffic conditioning module
 */

int altq_cdnr_enabled = 0;

/* cdnr_list keeps all cdnr's allocated. */
static LIST_HEAD(, top_cdnr) tcb_list;

static int altq_cdnr_input(struct mbuf *, int);
static struct top_cdnr *tcb_lookup(char *ifname);
static struct cdnr_block *cdnr_handle2cb(u_long);
static u_long cdnr_cb2handle(struct cdnr_block *);
static void *cdnr_cballoc(struct top_cdnr *, int,
       struct tc_action *(*)(struct cdnr_block *, struct cdnr_pktinfo *));
static void cdnr_cbdestroy(void *);
static int tca_verify_action(struct tc_action *);
static void tca_import_action(struct tc_action *, struct tc_action *);
static void tca_invalidate_action(struct tc_action *);

static int generic_element_destroy(struct cdnr_block *);
static struct top_cdnr *top_create(struct ifaltq *);
static int top_destroy(struct top_cdnr *);
static struct cdnr_block *element_create(struct top_cdnr *,
					      struct tc_action *);
static int element_destroy(struct cdnr_block *);
static void tb_import_profile(struct tbe *, struct tb_profile *);
static struct tbmeter *tbm_create(struct top_cdnr *, struct tb_profile *,
			   struct tc_action *, struct tc_action *);
static int tbm_destroy(struct tbmeter *);
static struct tc_action *tbm_input(struct cdnr_block *,
					struct cdnr_pktinfo *);
static struct trtcm *trtcm_create(struct top_cdnr *,
		  struct tb_profile *, struct tb_profile *,
		  struct tc_action *, struct tc_action *, struct tc_action *,
		  int);
static int trtcm_destroy(struct trtcm *);
static struct tc_action *trtcm_input(struct cdnr_block *,
					  struct cdnr_pktinfo *);
static struct tswtcm *tswtcm_create(struct top_cdnr *,
		  u_int32_t, u_int32_t, u_int32_t,
		  struct tc_action *, struct tc_action *, struct tc_action *);
static int tswtcm_destroy(struct tswtcm *);
static struct tc_action *tswtcm_input(struct cdnr_block *,
					   struct cdnr_pktinfo *);

static int cdnrcmd_if_attach(char *);
static int cdnrcmd_if_detach(char *);
static int cdnrcmd_add_element(struct cdnr_add_element *);
static int cdnrcmd_delete_element(struct cdnr_delete_element *);
static int cdnrcmd_add_tbm(struct cdnr_add_tbmeter *);
static int cdnrcmd_modify_tbm(struct cdnr_modify_tbmeter *);
static int cdnrcmd_tbm_stats(struct cdnr_tbmeter_stats *);
static int cdnrcmd_add_trtcm(struct cdnr_add_trtcm *);
static int cdnrcmd_modify_trtcm(struct cdnr_modify_trtcm *);
static int cdnrcmd_tcm_stats(struct cdnr_tcm_stats *);
static int cdnrcmd_add_tswtcm(struct cdnr_add_tswtcm *);
static int cdnrcmd_modify_tswtcm(struct cdnr_modify_tswtcm *);
static int cdnrcmd_get_stats(struct cdnr_get_stats *);

#if 1
/* dummy */
int cdnr_dummy(void);

int cdnr_dummy(void)
{
	altq_cdnr_input(NULL, 0);

	cdnrcmd_if_attach(NULL);
	cdnrcmd_if_detach(NULL);
	cdnrcmd_add_element(NULL);
	cdnrcmd_delete_element(NULL);
	cdnrcmd_add_tbm(NULL);
	cdnrcmd_modify_tbm(NULL);
	cdnrcmd_tbm_stats(NULL);
	cdnrcmd_add_trtcm(NULL);
	cdnrcmd_modify_trtcm(NULL);
	cdnrcmd_tcm_stats(NULL);
	cdnrcmd_add_tswtcm(NULL);
	cdnrcmd_modify_tswtcm(NULL);
	cdnrcmd_get_stats(NULL);
	return (0);
}

#endif

/*
 * top level input function called from ip_input.
 * should be called before converting header fields to host-byte-order.
 */
int
altq_cdnr_input(m, af)
	struct mbuf	*m;
	int		af;	/* address family */
{
	struct ifnet		*ifp;
	struct ip		*ip;
	struct top_cdnr		*top;
	struct tc_action	*tca;
	struct cdnr_block	*cb;
	struct cdnr_pktinfo	pktinfo;

	ifp = m->m_pkthdr.rcvif;
	if (!ALTQ_IS_CNDTNING(&ifp->if_snd))
		/* traffic conditioner is not enabled on this interface */
		return (1);

	top = ifp->if_snd.altq_cdnr;

	ip = mtod(m, struct ip *);
#ifdef INET6
	if (af == AF_INET6) {
		u_int32_t flowlabel;

		flowlabel = ((struct ip6_hdr *)ip)->ip6_flow;
		pktinfo.pkt_dscp = (ntohl(flowlabel) >> 20) & DSCP_MASK;
	} else
#endif
		pktinfo.pkt_dscp = ip->ip_tos & DSCP_MASK;
	pktinfo.pkt_len = m_pktlen(m);

	tca = NULL;

#if 0
	cb = acc_classify(&top->tc_classifier, m, af);
#endif
	if (cb != NULL)
		tca = &cb->cb_action;

	if (tca == NULL)
		tca = &top->tc_block.cb_action;

	while (1) {
		PKTCNTR_ADD(&top->tc_cnts[tca->tca_code], pktinfo.pkt_len);

		switch (tca->tca_code) {
		case TCACODE_PASS:
			return (1);
		case TCACODE_DROP:
			m_freem(m);
			return (0);
		case TCACODE_RETURN:
			return (0);
		case TCACODE_MARK:
#ifdef INET6
			if (af == AF_INET6) {
				struct ip6_hdr *ip6 = (struct ip6_hdr *)ip;
				u_int32_t flowlabel;

				flowlabel = ntohl(ip6->ip6_flow);
				flowlabel = (tca->tca_dscp << 20) |
					(flowlabel & ~(DSCP_MASK << 20));
				ip6->ip6_flow = htonl(flowlabel);
			} else
#endif
				ip->ip_tos = tca->tca_dscp |
					(ip->ip_tos & DSCP_CUMASK);
			return (1);
		case TCACODE_NEXT:
			cb = tca->tca_next;
			tca = (*cb->cb_input)(cb, &pktinfo);
			break;
		case TCACODE_NONE:
		default:
			return (1);
		}
	}
}

static struct top_cdnr *
tcb_lookup(ifname)
	char *ifname;
{
	struct top_cdnr *top;
	struct ifnet *ifp;

	if ((ifp = ifunit(ifname)) != NULL)
		LIST_FOREACH(top, &tcb_list, tc_next)
			if (top->tc_ifq->altq_ifp == ifp)
				return (top);
	return (NULL);
}

static struct cdnr_block *
cdnr_handle2cb(handle)
	u_long handle;
{
	struct cdnr_block *cb;

	cb = (struct cdnr_block *)handle;
	if (handle != ALIGN(cb))
		return (NULL);

	if (cb == NULL || cb->cb_handle != handle)
		return (NULL);
	return (cb);
}

static u_long
cdnr_cb2handle(cb)
	struct cdnr_block *cb;
{
	return (cb->cb_handle);
}

static void *
cdnr_cballoc(top, type, input_func)
	struct top_cdnr *top;
	int type;
	struct tc_action *(*input_func)(struct cdnr_block *,
					struct cdnr_pktinfo *);
{
	struct cdnr_block *cb;
	int size;

	switch (type) {
	case TCETYPE_TOP:
		size = sizeof(struct top_cdnr);
		break;
	case TCETYPE_ELEMENT:
		size = sizeof(struct cdnr_block);
		break;
	case TCETYPE_TBMETER:
		size = sizeof(struct tbmeter);
		break;
	case TCETYPE_TRTCM:
		size = sizeof(struct trtcm);
		break;
	case TCETYPE_TSWTCM:
		size = sizeof(struct tswtcm);
		break;
	default:
		return (NULL);
	}

	MALLOC(cb, struct cdnr_block *, size, M_DEVBUF, M_WAITOK);
	if (cb == NULL)
		return (NULL);
	bzero(cb, size);

	cb->cb_len = size;
	cb->cb_type = type;
	cb->cb_ref = 0;
	cb->cb_handle = (u_long)cb;
	if (top == NULL)
		cb->cb_top = (struct top_cdnr *)cb;
	else
		cb->cb_top = top;

	if (input_func != NULL) {
		/*
		 * if this cdnr has an action function,
		 * make tc_action to call itself.
		 */
		cb->cb_action.tca_code = TCACODE_NEXT;
		cb->cb_action.tca_next = cb;
		cb->cb_input = input_func;
	} else
		cb->cb_action.tca_code = TCACODE_NONE;

	/* if this isn't top, register the element to the top level cdnr */
	if (top != NULL)
		LIST_INSERT_HEAD(&top->tc_elements, cb, cb_next);

	return ((void *)cb);
}

static void
cdnr_cbdestroy(cblock)
	void *cblock;
{
	struct cdnr_block *cb = cblock;

	/* remove from the top level cdnr */
	if (cb->cb_top != cblock)
		LIST_REMOVE(cb, cb_next);

	FREE(cb, M_DEVBUF);
}

/*
 * conditioner common destroy routine
 */
static int
generic_element_destroy(cb)
	struct cdnr_block *cb;
{
	int error = 0;

	switch (cb->cb_type) {
	case TCETYPE_TOP:
		error = top_destroy((struct top_cdnr *)cb);
		break;
	case TCETYPE_ELEMENT:
		error = element_destroy(cb);
		break;
	case TCETYPE_TBMETER:
		error = tbm_destroy((struct tbmeter *)cb);
		break;
	case TCETYPE_TRTCM:
		error = trtcm_destroy((struct trtcm *)cb);
		break;
	case TCETYPE_TSWTCM:
		error = tswtcm_destroy((struct tswtcm *)cb);
		break;
	default:
		error = EINVAL;
	}
	return (error);
}

static int
tca_verify_action(utca)
	struct tc_action *utca;
{
	switch (utca->tca_code) {
	case TCACODE_PASS:
	case TCACODE_DROP:
	case TCACODE_MARK:
		/* these are ok */
		break;

	case TCACODE_HANDLE:
		/* verify handle value */
		if (cdnr_handle2cb(utca->tca_handle) == NULL)
			return (-1);
		break;

	case TCACODE_NONE:
	case TCACODE_RETURN:
	case TCACODE_NEXT:
	default:
		/* should not be passed from a user */
		return (-1);
	}
	return (0);
}

static void
tca_import_action(ktca, utca)
	struct tc_action *ktca, *utca;
{
	struct cdnr_block *cb;

	*ktca = *utca;
	if (ktca->tca_code == TCACODE_HANDLE) {
		cb = cdnr_handle2cb(ktca->tca_handle);
		if (cb == NULL) {
			ktca->tca_code = TCACODE_NONE;
			return;
		}
		ktca->tca_code = TCACODE_NEXT;
		ktca->tca_next = cb;
		cb->cb_ref++;
	} else if (ktca->tca_code == TCACODE_MARK) {
		ktca->tca_dscp &= DSCP_MASK;
	}
	return;
}

static void
tca_invalidate_action(tca)
	struct tc_action *tca;
{
	struct cdnr_block *cb;

	if (tca->tca_code == TCACODE_NEXT) {
		cb = tca->tca_next;
		if (cb == NULL)
			return;
		cb->cb_ref--;
	}
	tca->tca_code = TCACODE_NONE;
}

/*
 * top level traffic conditioner
 */
static struct top_cdnr *
top_create(ifq)
	struct ifaltq *ifq;
{
	struct top_cdnr *top;

	if ((top = cdnr_cballoc(NULL, TCETYPE_TOP, NULL)) == NULL)
		return (NULL);

	top->tc_ifq = ifq;
	/* set default action for the top level conditioner */
	top->tc_block.cb_action.tca_code = TCACODE_PASS;

	LIST_INSERT_HEAD(&tcb_list, top, tc_next);

	ifq->altq_cdnr = top;

	return (top);
}

static int
top_destroy(top)
	struct top_cdnr *top;
{
	struct cdnr_block *cb;

	if (ALTQ_IS_CNDTNING(top->tc_ifq))
		ALTQ_CLEAR_CNDTNING(top->tc_ifq);
	top->tc_ifq->altq_cdnr = NULL;

	/*
	 * destroy all the conditioner elements belonging to this interface
	 */
	while ((cb = LIST_FIRST(&top->tc_elements)) != NULL) {
		while (cb != NULL && cb->cb_ref > 0)
			cb = LIST_NEXT(cb, cb_next);
		if (cb != NULL)
			generic_element_destroy(cb);
	}

	LIST_REMOVE(top, tc_next);

	cdnr_cbdestroy(top);

	/* if there is no active conditioner, remove the input hook */
	if (altq_input != NULL) {
		LIST_FOREACH(top, &tcb_list, tc_next)
			if (ALTQ_IS_CNDTNING(top->tc_ifq))
				break;
		if (top == NULL)
			altq_input = NULL;
	}

	return (0);
}

/*
 * simple tc elements without input function (e.g., dropper and makers).
 */
static struct cdnr_block *
element_create(top, action)
	struct top_cdnr *top;
	struct tc_action *action;
{
	struct cdnr_block *cb;

	if (tca_verify_action(action) < 0)
		return (NULL);

	if ((cb = cdnr_cballoc(top, TCETYPE_ELEMENT, NULL)) == NULL)
		return (NULL);

	tca_import_action(&cb->cb_action, action);

	return (cb);
}

static int
element_destroy(cb)
	struct cdnr_block *cb;
{
	if (cb->cb_ref > 0)
		return (EBUSY);

	tca_invalidate_action(&cb->cb_action);

	cdnr_cbdestroy(cb);
	return (0);
}

/*
 * internal representation of token bucket parameters
 *	rate:	byte_per_unittime << 32
 *		(((bits_per_sec) / 8) << 32) / machclk_freq
 *	depth:	byte << 32
 *
 */
#define	TB_SHIFT	32
#define	TB_SCALE(x)	((u_int64_t)(x) << TB_SHIFT)
#define	TB_UNSCALE(x)	((x) >> TB_SHIFT)

static void
tb_import_profile(tb, profile)
	struct tbe *tb;
	struct tb_profile *profile;
{
	tb->rate = TB_SCALE(profile->rate / 8) / machclk_freq;
	tb->depth = TB_SCALE(profile->depth);
	if (tb->rate > 0)
		tb->filluptime = tb->depth / tb->rate;
	else
		tb->filluptime = 0xffffffffffffffffLL;
	tb->token = tb->depth;
	tb->last = read_machclk();
}

/*
 * simple token bucket meter
 */
static struct tbmeter *
tbm_create(top, profile, in_action, out_action)
	struct top_cdnr *top;
	struct tb_profile *profile;
	struct tc_action *in_action, *out_action;
{
	struct tbmeter *tbm = NULL;

	if (tca_verify_action(in_action) < 0
	    || tca_verify_action(out_action) < 0)
		return (NULL);

	if ((tbm = cdnr_cballoc(top, TCETYPE_TBMETER,
				tbm_input)) == NULL)
		return (NULL);

	tb_import_profile(&tbm->tb, profile);

	tca_import_action(&tbm->in_action, in_action);
	tca_import_action(&tbm->out_action, out_action);

	return (tbm);
}

static int
tbm_destroy(tbm)
	struct tbmeter *tbm;
{
	if (tbm->cdnrblk.cb_ref > 0)
		return (EBUSY);

	tca_invalidate_action(&tbm->in_action);
	tca_invalidate_action(&tbm->out_action);

	cdnr_cbdestroy(tbm);
	return (0);
}

static struct tc_action *
tbm_input(cb, pktinfo)
	struct cdnr_block *cb;
	struct cdnr_pktinfo *pktinfo;
{
	struct tbmeter *tbm = (struct tbmeter *)cb;
	u_int64_t	len;
	u_int64_t	interval, now;

	len = TB_SCALE(pktinfo->pkt_len);

	if (tbm->tb.token < len) {
		now = read_machclk();
		interval = now - tbm->tb.last;
		if (interval >= tbm->tb.filluptime)
			tbm->tb.token = tbm->tb.depth;
		else {
			tbm->tb.token += interval * tbm->tb.rate;
			if (tbm->tb.token > tbm->tb.depth)
				tbm->tb.token = tbm->tb.depth;
		}
		tbm->tb.last = now;
	}

	if (tbm->tb.token < len) {
		PKTCNTR_ADD(&tbm->out_cnt, pktinfo->pkt_len);
		return (&tbm->out_action);
	}

	tbm->tb.token -= len;
	PKTCNTR_ADD(&tbm->in_cnt, pktinfo->pkt_len);
	return (&tbm->in_action);
}

/*
 * two rate three color marker
 * as described in draft-heinanen-diffserv-trtcm-01.txt
 */
static struct trtcm *
trtcm_create(top, cmtd_profile, peak_profile,
	     green_action, yellow_action, red_action, coloraware)
	struct top_cdnr *top;
	struct tb_profile *cmtd_profile, *peak_profile;
	struct tc_action *green_action, *yellow_action, *red_action;
	int	coloraware;
{
	struct trtcm *tcm = NULL;

	if (tca_verify_action(green_action) < 0
	    || tca_verify_action(yellow_action) < 0
	    || tca_verify_action(red_action) < 0)
		return (NULL);

	if ((tcm = cdnr_cballoc(top, TCETYPE_TRTCM,
				trtcm_input)) == NULL)
		return (NULL);

	tb_import_profile(&tcm->cmtd_tb, cmtd_profile);
	tb_import_profile(&tcm->peak_tb, peak_profile);

	tca_import_action(&tcm->green_action, green_action);
	tca_import_action(&tcm->yellow_action, yellow_action);
	tca_import_action(&tcm->red_action, red_action);

	/* set dscps to use */
	if (tcm->green_action.tca_code == TCACODE_MARK)
		tcm->green_dscp = tcm->green_action.tca_dscp & DSCP_MASK;
	else
		tcm->green_dscp = DSCP_AF11;
	if (tcm->yellow_action.tca_code == TCACODE_MARK)
		tcm->yellow_dscp = tcm->yellow_action.tca_dscp & DSCP_MASK;
	else
		tcm->yellow_dscp = DSCP_AF12;
	if (tcm->red_action.tca_code == TCACODE_MARK)
		tcm->red_dscp = tcm->red_action.tca_dscp & DSCP_MASK;
	else
		tcm->red_dscp = DSCP_AF13;

	tcm->coloraware = coloraware;

	return (tcm);
}

static int
trtcm_destroy(tcm)
	struct trtcm *tcm;
{
	if (tcm->cdnrblk.cb_ref > 0)
		return (EBUSY);

	tca_invalidate_action(&tcm->green_action);
	tca_invalidate_action(&tcm->yellow_action);
	tca_invalidate_action(&tcm->red_action);

	cdnr_cbdestroy(tcm);
	return (0);
}

static struct tc_action *
trtcm_input(cb, pktinfo)
	struct cdnr_block *cb;
	struct cdnr_pktinfo *pktinfo;
{
	struct trtcm *tcm = (struct trtcm *)cb;
	u_int64_t	len;
	u_int64_t	interval, now;
	u_int8_t	color;

	len = TB_SCALE(pktinfo->pkt_len);
	if (tcm->coloraware) {
		color = pktinfo->pkt_dscp;
		if (color != tcm->yellow_dscp && color != tcm->red_dscp)
			color = tcm->green_dscp;
	} else {
		/* if color-blind, precolor it as green */
		color = tcm->green_dscp;
	}

	now = read_machclk();
	if (tcm->cmtd_tb.token < len) {
		interval = now - tcm->cmtd_tb.last;
		if (interval >= tcm->cmtd_tb.filluptime)
			tcm->cmtd_tb.token = tcm->cmtd_tb.depth;
		else {
			tcm->cmtd_tb.token += interval * tcm->cmtd_tb.rate;
			if (tcm->cmtd_tb.token > tcm->cmtd_tb.depth)
				tcm->cmtd_tb.token = tcm->cmtd_tb.depth;
		}
		tcm->cmtd_tb.last = now;
	}
	if (tcm->peak_tb.token < len) {
		interval = now - tcm->peak_tb.last;
		if (interval >= tcm->peak_tb.filluptime)
			tcm->peak_tb.token = tcm->peak_tb.depth;
		else {
			tcm->peak_tb.token += interval * tcm->peak_tb.rate;
			if (tcm->peak_tb.token > tcm->peak_tb.depth)
				tcm->peak_tb.token = tcm->peak_tb.depth;
		}
		tcm->peak_tb.last = now;
	}

	if (color == tcm->red_dscp || tcm->peak_tb.token < len) {
		pktinfo->pkt_dscp = tcm->red_dscp;
		PKTCNTR_ADD(&tcm->red_cnt, pktinfo->pkt_len);
		return (&tcm->red_action);
	}

	if (color == tcm->yellow_dscp || tcm->cmtd_tb.token < len) {
		pktinfo->pkt_dscp = tcm->yellow_dscp;
		tcm->peak_tb.token -= len;
		PKTCNTR_ADD(&tcm->yellow_cnt, pktinfo->pkt_len);
		return (&tcm->yellow_action);
	}

	pktinfo->pkt_dscp = tcm->green_dscp;
	tcm->cmtd_tb.token -= len;
	tcm->peak_tb.token -= len;
	PKTCNTR_ADD(&tcm->green_cnt, pktinfo->pkt_len);
	return (&tcm->green_action);
}

/*
 * time sliding window three color marker
 * as described in draft-fang-diffserv-tc-tswtcm-00.txt
 */
static struct tswtcm *
tswtcm_create(top, cmtd_rate, peak_rate, avg_interval,
	      green_action, yellow_action, red_action)
	struct top_cdnr *top;
	u_int32_t	cmtd_rate, peak_rate, avg_interval;
	struct tc_action *green_action, *yellow_action, *red_action;
{
	struct tswtcm *tsw;

	if (tca_verify_action(green_action) < 0
	    || tca_verify_action(yellow_action) < 0
	    || tca_verify_action(red_action) < 0)
		return (NULL);

	if ((tsw = cdnr_cballoc(top, TCETYPE_TSWTCM,
				tswtcm_input)) == NULL)
		return (NULL);

	tca_import_action(&tsw->green_action, green_action);
	tca_import_action(&tsw->yellow_action, yellow_action);
	tca_import_action(&tsw->red_action, red_action);

	/* set dscps to use */
	if (tsw->green_action.tca_code == TCACODE_MARK)
		tsw->green_dscp = tsw->green_action.tca_dscp & DSCP_MASK;
	else
		tsw->green_dscp = DSCP_AF11;
	if (tsw->yellow_action.tca_code == TCACODE_MARK)
		tsw->yellow_dscp = tsw->yellow_action.tca_dscp & DSCP_MASK;
	else
		tsw->yellow_dscp = DSCP_AF12;
	if (tsw->red_action.tca_code == TCACODE_MARK)
		tsw->red_dscp = tsw->red_action.tca_dscp & DSCP_MASK;
	else
		tsw->red_dscp = DSCP_AF13;

	/* convert rates from bits/sec to bytes/sec */
	tsw->cmtd_rate = cmtd_rate / 8;
	tsw->peak_rate = peak_rate / 8;
	tsw->avg_rate = 0;

	/* timewin is converted from msec to machine clock unit */
	tsw->timewin = (u_int64_t)machclk_freq * avg_interval / 1000;

	return (tsw);
}

static int
tswtcm_destroy(tsw)
	struct tswtcm *tsw;
{
	if (tsw->cdnrblk.cb_ref > 0)
		return (EBUSY);

	tca_invalidate_action(&tsw->green_action);
	tca_invalidate_action(&tsw->yellow_action);
	tca_invalidate_action(&tsw->red_action);

	cdnr_cbdestroy(tsw);
	return (0);
}

static struct tc_action *
tswtcm_input(cb, pktinfo)
	struct cdnr_block *cb;
	struct cdnr_pktinfo *pktinfo;
{
	struct tswtcm	*tsw = (struct tswtcm *)cb;
	int		len;
	u_int32_t	avg_rate;
	u_int64_t	interval, now, tmp;

	/*
	 * rate estimator
	 */
	len = pktinfo->pkt_len;
	now = read_machclk();

	interval = now - tsw->t_front;
	/*
	 * calculate average rate:
	 *	avg = (avg * timewin + pkt_len)/(timewin + interval)
	 * pkt_len needs to be multiplied by machclk_freq in order to
	 * get (bytes/sec).
	 * note: when avg_rate (bytes/sec) and timewin (machclk unit) are
	 * less than 32 bits, the following 64-bit operation has enough
	 * precision.
	 */
	tmp = ((u_int64_t)tsw->avg_rate * tsw->timewin
	       + (u_int64_t)len * machclk_freq) / (tsw->timewin + interval);
	tsw->avg_rate = avg_rate = (u_int32_t)tmp;
	tsw->t_front = now;

	/*
	 * marker
	 */
	if (avg_rate > tsw->cmtd_rate) {
		u_int32_t randval = random() % avg_rate;

		if (avg_rate > tsw->peak_rate) {
			if (randval < avg_rate - tsw->peak_rate) {
				/* mark red */
				pktinfo->pkt_dscp = tsw->red_dscp;
				PKTCNTR_ADD(&tsw->red_cnt, len);
				return (&tsw->red_action);
			} else if (randval < avg_rate - tsw->cmtd_rate)
				goto mark_yellow;
		} else {
			/* peak_rate >= avg_rate > cmtd_rate */
			if (randval < avg_rate - tsw->cmtd_rate) {
			mark_yellow:
				pktinfo->pkt_dscp = tsw->yellow_dscp;
				PKTCNTR_ADD(&tsw->yellow_cnt, len);
				return (&tsw->yellow_action);
			}
		}
	}

	/* mark green */
	pktinfo->pkt_dscp = tsw->green_dscp;
	PKTCNTR_ADD(&tsw->green_cnt, len);
	return (&tsw->green_action);
}

/*
 * ioctl requests
 */
static int
cdnrcmd_if_attach(ifname)
	char *ifname;
{
	struct ifnet *ifp;
	struct top_cdnr *top;

	if ((ifp = ifunit(ifname)) == NULL)
		return (EBADF);

	if (ifp->if_snd.altq_cdnr != NULL)
		return (EBUSY);

	if ((top = top_create(&ifp->if_snd)) == NULL)
		return (ENOMEM);
	return (0);
}

static int
cdnrcmd_if_detach(ifname)
	char *ifname;
{
	struct top_cdnr *top;

	if ((top = tcb_lookup(ifname)) == NULL)
		return (EBADF);

	return top_destroy(top);
}

static int
cdnrcmd_add_element(ap)
	struct cdnr_add_element *ap;
{
	struct top_cdnr *top;
	struct cdnr_block *cb;

	if ((top = tcb_lookup(ap->iface.cdnr_ifname)) == NULL)
		return (EBADF);

	cb = element_create(top, &ap->action);
	if (cb == NULL)
		return (EINVAL);
	/* return a class handle to the user */
	ap->cdnr_handle = cdnr_cb2handle(cb);
	return (0);
}

static int
cdnrcmd_delete_element(ap)
	struct cdnr_delete_element *ap;
{
	struct top_cdnr *top;
	struct cdnr_block *cb;

	if ((top = tcb_lookup(ap->iface.cdnr_ifname)) == NULL)
		return (EBADF);

	if ((cb = cdnr_handle2cb(ap->cdnr_handle)) == NULL)
		return (EINVAL);

	if (cb->cb_type != TCETYPE_ELEMENT)
		return generic_element_destroy(cb);

	return element_destroy(cb);
}

static int
cdnrcmd_add_tbm(ap)
	struct cdnr_add_tbmeter *ap;
{
	struct top_cdnr *top;
	struct tbmeter *tbm;

	if ((top = tcb_lookup(ap->iface.cdnr_ifname)) == NULL)
		return (EBADF);

	tbm = tbm_create(top, &ap->profile, &ap->in_action, &ap->out_action);
	if (tbm == NULL)
		return (EINVAL);
	/* return a class handle to the user */
	ap->cdnr_handle = cdnr_cb2handle(&tbm->cdnrblk);
	return (0);
}

static int
cdnrcmd_modify_tbm(ap)
	struct cdnr_modify_tbmeter *ap;
{
	struct tbmeter *tbm;

	if ((tbm = (struct tbmeter *)cdnr_handle2cb(ap->cdnr_handle)) == NULL)
		return (EINVAL);

	tb_import_profile(&tbm->tb, &ap->profile);

	return (0);
}

static int
cdnrcmd_tbm_stats(ap)
	struct cdnr_tbmeter_stats *ap;
{
	struct tbmeter *tbm;

	if ((tbm = (struct tbmeter *)cdnr_handle2cb(ap->cdnr_handle)) == NULL)
		return (EINVAL);

	ap->in_cnt = tbm->in_cnt;
	ap->out_cnt = tbm->out_cnt;

	return (0);
}

static int
cdnrcmd_add_trtcm(ap)
	struct cdnr_add_trtcm *ap;
{
	struct top_cdnr *top;
	struct trtcm *tcm;

	if ((top = tcb_lookup(ap->iface.cdnr_ifname)) == NULL)
		return (EBADF);

	tcm = trtcm_create(top, &ap->cmtd_profile, &ap->peak_profile,
			   &ap->green_action, &ap->yellow_action,
			   &ap->red_action, ap->coloraware);
	if (tcm == NULL)
		return (EINVAL);

	/* return a class handle to the user */
	ap->cdnr_handle = cdnr_cb2handle(&tcm->cdnrblk);
	return (0);
}

static int
cdnrcmd_modify_trtcm(ap)
	struct cdnr_modify_trtcm *ap;
{
	struct trtcm *tcm;

	if ((tcm = (struct trtcm *)cdnr_handle2cb(ap->cdnr_handle)) == NULL)
		return (EINVAL);

	tb_import_profile(&tcm->cmtd_tb, &ap->cmtd_profile);
	tb_import_profile(&tcm->peak_tb, &ap->peak_profile);

	return (0);
}

static int
cdnrcmd_tcm_stats(ap)
	struct cdnr_tcm_stats *ap;
{
	struct cdnr_block *cb;

	if ((cb = cdnr_handle2cb(ap->cdnr_handle)) == NULL)
		return (EINVAL);

	if (cb->cb_type == TCETYPE_TRTCM) {
	    struct trtcm *tcm = (struct trtcm *)cb;

	    ap->green_cnt = tcm->green_cnt;
	    ap->yellow_cnt = tcm->yellow_cnt;
	    ap->red_cnt = tcm->red_cnt;
	} else if (cb->cb_type == TCETYPE_TSWTCM) {
	    struct tswtcm *tsw = (struct tswtcm *)cb;

	    ap->green_cnt = tsw->green_cnt;
	    ap->yellow_cnt = tsw->yellow_cnt;
	    ap->red_cnt = tsw->red_cnt;
	} else
	    return (EINVAL);

	return (0);
}

static int
cdnrcmd_add_tswtcm(ap)
	struct cdnr_add_tswtcm *ap;
{
	struct top_cdnr *top;
	struct tswtcm *tsw;

	if ((top = tcb_lookup(ap->iface.cdnr_ifname)) == NULL)
		return (EBADF);

	if (ap->cmtd_rate > ap->peak_rate)
		return (EINVAL);

	tsw = tswtcm_create(top, ap->cmtd_rate, ap->peak_rate,
			    ap->avg_interval, &ap->green_action,
			    &ap->yellow_action, &ap->red_action);
	if (tsw == NULL)
	    return (EINVAL);

	/* return a class handle to the user */
	ap->cdnr_handle = cdnr_cb2handle(&tsw->cdnrblk);
	return (0);
}

static int
cdnrcmd_modify_tswtcm(ap)
	struct cdnr_modify_tswtcm *ap;
{
	struct tswtcm *tsw;

	if ((tsw = (struct tswtcm *)cdnr_handle2cb(ap->cdnr_handle)) == NULL)
		return (EINVAL);

	if (ap->cmtd_rate > ap->peak_rate)
		return (EINVAL);

	/* convert rates from bits/sec to bytes/sec */
	tsw->cmtd_rate = ap->cmtd_rate / 8;
	tsw->peak_rate = ap->peak_rate / 8;
	tsw->avg_rate = 0;

	/* timewin is converted from msec to machine clock unit */
	tsw->timewin = (u_int64_t)machclk_freq * ap->avg_interval / 1000;

	return (0);
}

static int
cdnrcmd_get_stats(ap)
	struct cdnr_get_stats *ap;
{
	struct top_cdnr *top;
	struct cdnr_block *cb;
	struct tbmeter *tbm;
	struct trtcm *tcm;
	struct tswtcm *tsw;
	struct tce_stats tce, *usp;
	int error, n, nskip, nelements;

	if ((top = tcb_lookup(ap->iface.cdnr_ifname)) == NULL)
		return (EBADF);

	/* copy action stats */
	bcopy(top->tc_cnts, ap->cnts, sizeof(ap->cnts));

	/* stats for each element */
	nelements = ap->nelements;
	usp = ap->tce_stats;
	if (nelements <= 0 || usp == NULL)
		return (0);

	nskip = ap->nskip;
	n = 0;
	LIST_FOREACH(cb, &top->tc_elements, cb_next) {
		if (nskip > 0) {
			nskip--;
			continue;
		}

		bzero(&tce, sizeof(tce));
		tce.tce_handle = cb->cb_handle;
		tce.tce_type = cb->cb_type;
		switch (cb->cb_type) {
		case TCETYPE_TBMETER:
			tbm = (struct tbmeter *)cb;
			tce.tce_cnts[0] = tbm->in_cnt;
			tce.tce_cnts[1] = tbm->out_cnt;
			break;
		case TCETYPE_TRTCM:
			tcm = (struct trtcm *)cb;
			tce.tce_cnts[0] = tcm->green_cnt;
			tce.tce_cnts[1] = tcm->yellow_cnt;
			tce.tce_cnts[2] = tcm->red_cnt;
			break;
		case TCETYPE_TSWTCM:
			tsw = (struct tswtcm *)cb;
			tce.tce_cnts[0] = tsw->green_cnt;
			tce.tce_cnts[1] = tsw->yellow_cnt;
			tce.tce_cnts[2] = tsw->red_cnt;
			break;
		default:
			continue;
		}

		if ((error = copyout((caddr_t)&tce, (caddr_t)usp++,
				     sizeof(tce))) != 0)
			return (error);

		if (++n == nelements)
			break;
	}
	ap->nelements = n;

	return (0);
}