diff -urN a/tc/Makefile b/tc/Makefile
--- a/tc/Makefile	2000-04-16 19:42:53.000000000 +0200
+++ b/tc/Makefile	2004-01-04 23:24:39.000000000 +0100
@@ -26,7 +26,7 @@
 
 #TCMODULES += q_csz.o
 #TCMODULES += q_hpfq.o
-#TCMODULES += q_hfsc.o
+TCMODULES += q_hfsc.o
 
 TCOBJ += $(TCMODULES)
 
diff -urN a/tc/q_hfsc.c b/tc/q_hfsc.c
--- a/tc/q_hfsc.c	2000-04-16 19:42:54.000000000 +0200
+++ b/tc/q_hfsc.c	2004-01-25 14:42:43.000000000 +0100
@@ -1,12 +1,12 @@
 /*
- * q_hfsc.c		HFSC.
+ * q_hfsc.c	HFSC.
  *
  *		This program is free software; you can redistribute it and/or
  *		modify it under the terms of the GNU General Public License
  *		as published by the Free Software Foundation; either version
  *		2 of the License, or (at your option) any later version.
  *
- * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>; Patrick McHardy, <kaber@trash.ner>
  *
  */
 
@@ -19,36 +19,247 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <string.h>
+#include <math.h>
 
 #include "utils.h"
 #include "tc_util.h"
 
-static void explain()
+static int hfsc_get_sc(int *, char ***, struct tc_service_curve *);
+
+
+static void
+explain_qdisc(void)
+{
+	fprintf(stderr,
+		"Usage: ... hfsc [ default CLASSID ]\n"
+		"\n"
+		" default: default class for unclassified packets\n"
+	);
+}
+
+static void
+explain_class(void)
 {
-	fprintf(stderr, "Usage: ... hfsc \n");
+	fprintf(stderr, 
+		"Usage: ... hfsc [ rt SC ] [ ls SC ] [ ul SC ]\n"
+		"\n"
+		"SC := [ [ m1 BPS ] [ d SEC ] m2 BPS\n"
+		"\n"
+		" m1 : slope of first segment\n"
+		" d  : x-coordinate of intersection\n"
+		" m2 : slope of second segment\n"
+		"\n"
+		"Alternative format:\n"
+		"\n"
+		"SC := [ [ umax BYTE ] dmax SEC ] rate BPS\n"
+		"\n"
+		" umax : maximum unit of work\n"
+		" dmax : maximum delay\n"
+		" rate : rate\n"
+		"\n"
+	);
 }
 
-static void explain1(char *arg)
+static void
+explain1(char *arg)
 {
-	fprintf(stderr, "Illegal \"%s\"\n", arg);
+	fprintf(stderr, "HFSC: Illegal \"%s\"\n", arg);
 }
 
+static int
+hfsc_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n)
+{
+	struct tc_hfsc_qopt qopt;
+
+	memset(&qopt, 0, sizeof(qopt));
+
+	while (argc > 0) {
+		if (matches(*argv, "default") == 0) {
+			NEXT_ARG();
+			if (qopt.defcls != 0) {
+				fprintf(stderr, "HFSC: Double \"default\"\n");
+				return -1;
+			}
+			if (get_u16(&qopt.defcls, *argv, 16) < 0) {
+				explain1("default");
+				return -1;
+			}
+		} else if (matches(*argv, "help") == 0) {
+			explain_qdisc();
+			return -1;
+		} else {
+			fprintf(stderr, "HFSC: What is \"%s\" ?\n", *argv);
+			explain_qdisc();
+			return -1;
+		}
+		argc--, argv++;
+	}
 
-#define usage() return(-1)
+	addattr_l(n, 1024, TCA_OPTIONS, &qopt, sizeof(qopt));
+	return 0;
+}
 
-static int hfsc_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n)
+static int
+hfsc_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 {
-	return -1;
+	struct tc_hfsc_qopt *qopt;
+
+	if (opt == NULL)
+		return 0;
+	if (RTA_PAYLOAD(opt) < sizeof(*qopt))
+		return -1;
+	qopt = RTA_DATA(opt);
+	
+	if (qopt->defcls != 0)
+		fprintf(f, "default %x ", qopt->defcls);
+
+	return 0;
 }
 
-static int hfsc_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
+static int
+hfsc_print_xstats(struct qdisc_util *qu, FILE *f, struct rtattr *xstats)
 {
-	return -1;
+	struct tc_hfsc_stats *st;
+
+	if (xstats == NULL)
+		return 0;
+	if (RTA_PAYLOAD(xstats) < sizeof(*st))
+		return -1;
+	st = RTA_DATA(xstats);
+
+	fprintf(f, " period %u ", st->period);
+	if (st->work != 0)
+		fprintf(f, "work %llu bytes ", st->work);
+	if (st->rtwork != 0)
+		fprintf(f, "rtwork %llu bytes ", st->rtwork);
+	fprintf(f, "level %u ", st->level);
+	fprintf(f, "\n");
+
+	return 0;
 }
 
-static int hfsc_print_xstats(struct qdisc_util *qu, FILE *f, struct rtattr *xstats)
+static int
+hfsc_parse_class_opt(struct qdisc_util *qu, int argc, char **argv,
+                     struct nlmsghdr *n)
 {
-	return -1;
+	struct tc_service_curve rsc, fsc, usc;
+	int rsc_ok, fsc_ok, usc_ok;
+	struct rtattr *tail;
+
+	memset(&rsc, 0, sizeof(rsc));
+	memset(&fsc, 0, sizeof(fsc));
+	memset(&usc, 0, sizeof(usc));
+	rsc_ok = fsc_ok = usc_ok = 0;
+
+	while (argc > 0) {
+		if (matches(*argv, "rt") == 0) {
+			NEXT_ARG();
+			if (hfsc_get_sc(&argc, &argv, &rsc) < 0) {
+				explain1("rt");
+				return -1;
+			}
+			rsc_ok = 1;
+		} else if (matches(*argv, "ls") == 0) {
+			NEXT_ARG();
+			if (hfsc_get_sc(&argc, &argv, &fsc) < 0) {
+				explain1("ls");
+				return -1;
+			}
+			fsc_ok = 1;
+		} else if (matches(*argv, "ul") == 0) {
+			NEXT_ARG();
+			if (hfsc_get_sc(&argc, &argv, &usc) < 0) {
+				explain1("ul");
+				return -1;
+			}
+			usc_ok = 1;
+		} else if (matches(*argv, "help") == 0) {
+			explain_class();
+			return -1;
+		} else {
+			fprintf(stderr, "HFSC: What is \"%s\" ?\n", *argv);
+			explain_class();
+			return -1;
+		}
+		argc--, argv++;
+	}
+
+	if (!(rsc_ok || fsc_ok || usc_ok)) {
+		fprintf(stderr, "HFSC: no parameters given\n");
+		explain_class();
+		return -1;
+	}
+	if (usc_ok && !fsc_ok) {
+		fprintf(stderr, "HFSC: Upper-limit Service Curve without "
+		                "Link-Share Service Curve\n");
+		explain_class();
+		return -1;
+	}
+
+	tail = (struct rtattr*)(((void*)n) + NLMSG_ALIGN(n->nlmsg_len));
+
+	addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
+	if (rsc_ok)
+		addattr_l(n, 1024, TCA_HFSC_RSC, &rsc, sizeof(rsc));
+	if (fsc_ok)
+		addattr_l(n, 1024, TCA_HFSC_FSC, &fsc, sizeof(fsc));
+	if (usc_ok)
+		addattr_l(n, 1024, TCA_HFSC_USC, &usc, sizeof(usc));
+
+	tail->rta_len = (((void*)n) + NLMSG_ALIGN(n->nlmsg_len)) - (void*)tail;
+	return 0;
+}
+
+static void
+hfsc_print_sc(FILE *f, char *name, struct tc_service_curve *sc)
+{
+	SPRINT_BUF(b1);
+
+	fprintf(f, "%s ", name);
+	fprintf(f, "m1 %s ", sprint_rate(sc->m1, b1));
+	fprintf(f, "d %s ", sprint_usecs(sc->d, b1));
+	fprintf(f, "m2 %s ", sprint_rate(sc->m2, b1));
+}
+
+static int
+hfsc_print_class_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
+{
+	struct rtattr *tb[TCA_HFSC_MAX+1];
+	struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
+	
+	if (opt == NULL)
+		return 0;
+
+	memset(tb, 0, sizeof(tb));
+	parse_rtattr(tb, TCA_HFSC_MAX, RTA_DATA(opt), RTA_PAYLOAD(opt));
+
+	if (tb[TCA_HFSC_RSC]) {
+		if (RTA_PAYLOAD(tb[TCA_HFSC_RSC]) < sizeof(*rsc))
+			fprintf(stderr, "HFSC: truncated realtime option\n");
+		else
+			rsc = RTA_DATA(tb[TCA_HFSC_RSC]);
+	}
+	if (tb[TCA_HFSC_FSC]) {
+		if (RTA_PAYLOAD(tb[TCA_HFSC_FSC]) < sizeof(*fsc))
+			fprintf(stderr, "HFSC: truncated linkshare option\n");
+		else
+			fsc = RTA_DATA(tb[TCA_HFSC_FSC]);
+	}
+	if (tb[TCA_HFSC_USC]) {
+		if (RTA_PAYLOAD(tb[TCA_HFSC_USC]) < sizeof(*usc))
+			fprintf(stderr, "HFSC: truncated upperlimit option\n");
+		else
+			usc = RTA_DATA(tb[TCA_HFSC_USC]);
+	}
+
+	if (rsc != NULL)
+		hfsc_print_sc(f, "rt", rsc);
+	if (fsc != NULL)
+		hfsc_print_sc(f, "ls", fsc);
+	if (usc != NULL) 
+		hfsc_print_sc(f, "ul", usc);
+
+	return 0;
 }
 
 struct qdisc_util hfsc_util = {
@@ -57,5 +268,126 @@
 	hfsc_parse_opt,
 	hfsc_print_opt,
 	hfsc_print_xstats,
+	hfsc_parse_class_opt,
+	hfsc_print_class_opt,
 };
 
+static int
+hfsc_get_sc1(int *argcp, char ***argvp, struct tc_service_curve *sc)
+{
+	char **argv = *argvp;
+	int argc = *argcp;
+	unsigned int m1 = 0, d = 0, m2 = 0;
+
+	if (matches(*argv, "m1") == 0) {
+		NEXT_ARG();
+		if (get_rate(&m1, *argv) < 0) {
+			explain1("m1");
+			return -1;
+		}
+		NEXT_ARG();
+	}
+
+	if (matches(*argv, "d") == 0) {
+		NEXT_ARG();
+		if (get_usecs(&d, *argv) < 0) {
+			explain1("d");
+			return -1;
+		}
+		NEXT_ARG();
+	}
+
+	if (matches(*argv, "m2") == 0) {
+		NEXT_ARG();
+		if (get_rate(&m2, *argv) < 0) {
+			explain1("m2");
+			return -1;
+		}
+	} else
+		return -1;
+
+	sc->m1 = m1;
+	sc->d  = d;
+	sc->m2 = m2;
+
+	*argvp = argv;
+	*argcp = argc;
+	return 0;
+}
+
+static int
+hfsc_get_sc2(int *argcp, char ***argvp, struct tc_service_curve *sc)
+{
+	char **argv = *argvp;
+	int argc = *argcp;
+	unsigned int umax = 0, dmax = 0, rate = 0;
+
+	if (matches(*argv, "umax") == 0) {
+		NEXT_ARG();
+		if (get_size(&umax, *argv) < 0) {
+			explain1("umax");
+			return -1;
+		}
+		NEXT_ARG();
+	}
+
+	if (matches(*argv, "dmax") == 0) {
+		NEXT_ARG();
+		if (get_usecs(&dmax, *argv) < 0) {
+			explain1("dmax");
+			return -1;
+		}
+		NEXT_ARG();
+	}
+
+	if (matches(*argv, "rate") == 0) {
+		NEXT_ARG();
+		if (get_rate(&rate, *argv) < 0) {
+			explain1("rate");
+			return -1;
+		}
+	} else
+		return -1;
+
+	if (umax != 0 && dmax == 0) {
+		fprintf(stderr, "HFSC: umax given but dmax is zero.\n");
+		return -1;
+	}
+
+	if (dmax != 0 && ceil(umax * 1000000.0 / dmax) > rate) {
+		/*
+		 * concave curve, slope of first segment is umax/dmax,
+		 * intersection is at dmax
+		 */
+		sc->m1 = ceil(umax * 1000000.0 / dmax); /* in bps */
+		sc->d  = dmax; 
+		sc->m2 = rate; 
+	} else {
+		/*
+		 * convex curve, slope of first segment is 0, intersection 
+		 * is at dmax - umax / rate
+		 */
+		sc->m1 = 0;
+		sc->d  = ceil(dmax - umax * 1000000.0 / rate); /* in usec */
+		sc->m2 = rate;
+	}
+
+	*argvp = argv;
+	*argcp = argc;
+	return 0;
+}
+
+static int
+hfsc_get_sc(int *argcp, char ***argvp, struct tc_service_curve *sc)
+{
+	if (hfsc_get_sc1(argcp, argvp, sc) < 0 &&
+	    hfsc_get_sc2(argcp, argvp, sc) < 0)
+		return -1;
+
+	if (sc->m1 == 0 && sc->m2 == 0) {
+		fprintf(stderr, "HFSC: Service Curve has two zero slopes\n");
+		return -1;
+	}
+
+	return 0;
+}