1/*
2 * q_hfsc.c	HFSC.
3 *
4 *		This program is free software; you can redistribute it and/or
5 *		modify it under the terms of the GNU General Public License
6 *		as published by the Free Software Foundation; either version
7 *		2 of the License, or (at your option) any later version.
8 *
9 * Authors:	Patrick McHardy, <kaber@trash.net>
10 *
11 */
12
13#include <stdio.h>
14#include <stdlib.h>
15#include <unistd.h>
16#include <syslog.h>
17#include <fcntl.h>
18#include <sys/socket.h>
19#include <netinet/in.h>
20#include <arpa/inet.h>
21#include <string.h>
22#include <math.h>
23
24#include "utils.h"
25#include "tc_util.h"
26
27static int hfsc_get_sc(int *, char ***, struct tc_service_curve *);
28
29
30static void
31explain_qdisc(void)
32{
33	fprintf(stderr,
34		"Usage: ... hfsc [ default CLASSID ]\n"
35		"\n"
36		" default: default class for unclassified packets\n"
37	);
38}
39
40static void
41explain_class(void)
42{
43	fprintf(stderr,
44		"Usage: ... hfsc [ [ rt SC ] [ ls SC ] | [ sc SC ] ] [ ul SC ]\n"
45		"\n"
46		"SC := [ [ m1 BPS ] [ d SEC ] m2 BPS\n"
47		"\n"
48		" m1 : slope of first segment\n"
49		" d  : x-coordinate of intersection\n"
50		" m2 : slope of second segment\n"
51		"\n"
52		"Alternative format:\n"
53		"\n"
54		"SC := [ [ umax BYTE ] dmax SEC ] rate BPS\n"
55		"\n"
56		" umax : maximum unit of work\n"
57		" dmax : maximum delay\n"
58		" rate : rate\n"
59		"\n"
60	);
61}
62
63static void
64explain1(char *arg)
65{
66	fprintf(stderr, "HFSC: Illegal \"%s\"\n", arg);
67}
68
69static int
70hfsc_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n)
71{
72	struct tc_hfsc_qopt qopt;
73
74	memset(&qopt, 0, sizeof(qopt));
75
76	while (argc > 0) {
77		if (matches(*argv, "default") == 0) {
78			NEXT_ARG();
79			if (qopt.defcls != 0) {
80				fprintf(stderr, "HFSC: Double \"default\"\n");
81				return -1;
82			}
83			if (get_u16(&qopt.defcls, *argv, 16) < 0) {
84				explain1("default");
85				return -1;
86			}
87		} else if (matches(*argv, "help") == 0) {
88			explain_qdisc();
89			return -1;
90		} else {
91			fprintf(stderr, "HFSC: What is \"%s\" ?\n", *argv);
92			explain_qdisc();
93			return -1;
94		}
95		argc--, argv++;
96	}
97
98	addattr_l(n, 1024, TCA_OPTIONS, &qopt, sizeof(qopt));
99	return 0;
100}
101
102static int
103hfsc_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
104{
105	struct tc_hfsc_qopt *qopt;
106
107	if (opt == NULL)
108		return 0;
109	if (RTA_PAYLOAD(opt) < sizeof(*qopt))
110		return -1;
111	qopt = RTA_DATA(opt);
112
113	if (qopt->defcls != 0)
114		fprintf(f, "default %x ", qopt->defcls);
115
116	return 0;
117}
118
119static int
120hfsc_print_xstats(struct qdisc_util *qu, FILE *f, struct rtattr *xstats)
121{
122	struct tc_hfsc_stats *st;
123
124	if (xstats == NULL)
125		return 0;
126	if (RTA_PAYLOAD(xstats) < sizeof(*st))
127		return -1;
128	st = RTA_DATA(xstats);
129
130	fprintf(f, " period %u ", st->period);
131	if (st->work != 0)
132		fprintf(f, "work %llu bytes ", (unsigned long long) st->work);
133	if (st->rtwork != 0)
134		fprintf(f, "rtwork %llu bytes ", (unsigned long long) st->rtwork);
135	fprintf(f, "level %u ", st->level);
136	fprintf(f, "\n");
137
138	return 0;
139}
140
141static int
142hfsc_parse_class_opt(struct qdisc_util *qu, int argc, char **argv,
143                     struct nlmsghdr *n)
144{
145	struct tc_service_curve rsc, fsc, usc;
146	int rsc_ok, fsc_ok, usc_ok;
147	struct rtattr *tail;
148
149	memset(&rsc, 0, sizeof(rsc));
150	memset(&fsc, 0, sizeof(fsc));
151	memset(&usc, 0, sizeof(usc));
152	rsc_ok = fsc_ok = usc_ok = 0;
153
154	while (argc > 0) {
155		if (matches(*argv, "rt") == 0) {
156			NEXT_ARG();
157			if (hfsc_get_sc(&argc, &argv, &rsc) < 0) {
158				explain1("rt");
159				return -1;
160			}
161			rsc_ok = 1;
162		} else if (matches(*argv, "ls") == 0) {
163			NEXT_ARG();
164			if (hfsc_get_sc(&argc, &argv, &fsc) < 0) {
165				explain1("ls");
166				return -1;
167			}
168			fsc_ok = 1;
169		} else if (matches(*argv, "sc") == 0) {
170			NEXT_ARG();
171			if (hfsc_get_sc(&argc, &argv, &rsc) < 0) {
172				explain1("sc");
173				return -1;
174			}
175			memcpy(&fsc, &rsc, sizeof(fsc));
176			rsc_ok = 1;
177			fsc_ok = 1;
178		} else if (matches(*argv, "ul") == 0) {
179			NEXT_ARG();
180			if (hfsc_get_sc(&argc, &argv, &usc) < 0) {
181				explain1("ul");
182				return -1;
183			}
184			usc_ok = 1;
185		} else if (matches(*argv, "help") == 0) {
186			explain_class();
187			return -1;
188		} else {
189			fprintf(stderr, "HFSC: What is \"%s\" ?\n", *argv);
190			explain_class();
191			return -1;
192		}
193		argc--, argv++;
194	}
195
196	if (!(rsc_ok || fsc_ok || usc_ok)) {
197		fprintf(stderr, "HFSC: no parameters given\n");
198		explain_class();
199		return -1;
200	}
201	if (usc_ok && !fsc_ok) {
202		fprintf(stderr, "HFSC: Upper-limit Service Curve without "
203		                "Link-Share Service Curve\n");
204		explain_class();
205		return -1;
206	}
207
208	tail = NLMSG_TAIL(n);
209
210	addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
211	if (rsc_ok)
212		addattr_l(n, 1024, TCA_HFSC_RSC, &rsc, sizeof(rsc));
213	if (fsc_ok)
214		addattr_l(n, 1024, TCA_HFSC_FSC, &fsc, sizeof(fsc));
215	if (usc_ok)
216		addattr_l(n, 1024, TCA_HFSC_USC, &usc, sizeof(usc));
217
218	tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
219	return 0;
220}
221
222static void
223hfsc_print_sc(FILE *f, char *name, struct tc_service_curve *sc)
224{
225	SPRINT_BUF(b1);
226
227	fprintf(f, "%s ", name);
228	fprintf(f, "m1 %s ", sprint_rate(sc->m1, b1));
229	fprintf(f, "d %s ", sprint_usecs(sc->d, b1));
230	fprintf(f, "m2 %s ", sprint_rate(sc->m2, b1));
231}
232
233static int
234hfsc_print_class_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
235{
236	struct rtattr *tb[TCA_HFSC_MAX+1];
237	struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
238
239	if (opt == NULL)
240		return 0;
241
242	parse_rtattr_nested(tb, TCA_HFSC_MAX, opt);
243
244	if (tb[TCA_HFSC_RSC]) {
245		if (RTA_PAYLOAD(tb[TCA_HFSC_RSC]) < sizeof(*rsc))
246			fprintf(stderr, "HFSC: truncated realtime option\n");
247		else
248			rsc = RTA_DATA(tb[TCA_HFSC_RSC]);
249	}
250	if (tb[TCA_HFSC_FSC]) {
251		if (RTA_PAYLOAD(tb[TCA_HFSC_FSC]) < sizeof(*fsc))
252			fprintf(stderr, "HFSC: truncated linkshare option\n");
253		else
254			fsc = RTA_DATA(tb[TCA_HFSC_FSC]);
255	}
256	if (tb[TCA_HFSC_USC]) {
257		if (RTA_PAYLOAD(tb[TCA_HFSC_USC]) < sizeof(*usc))
258			fprintf(stderr, "HFSC: truncated upperlimit option\n");
259		else
260			usc = RTA_DATA(tb[TCA_HFSC_USC]);
261	}
262
263
264	if (rsc != NULL && fsc != NULL &&
265	    memcmp(rsc, fsc, sizeof(*rsc)) == 0)
266		hfsc_print_sc(f, "sc", rsc);
267	else {
268		if (rsc != NULL)
269			hfsc_print_sc(f, "rt", rsc);
270		if (fsc != NULL)
271			hfsc_print_sc(f, "ls", fsc);
272	}
273	if (usc != NULL)
274		hfsc_print_sc(f, "ul", usc);
275
276	return 0;
277}
278
279struct qdisc_util hfsc_qdisc_util = {
280	.id		= "hfsc",
281	.parse_qopt	= hfsc_parse_opt,
282	.print_qopt	= hfsc_print_opt,
283	.print_xstats	= hfsc_print_xstats,
284	.parse_copt	= hfsc_parse_class_opt,
285	.print_copt	= hfsc_print_class_opt,
286};
287
288static int
289hfsc_get_sc1(int *argcp, char ***argvp, struct tc_service_curve *sc)
290{
291	char **argv = *argvp;
292	int argc = *argcp;
293	unsigned int m1 = 0, d = 0, m2 = 0;
294
295	if (matches(*argv, "m1") == 0) {
296		NEXT_ARG();
297		if (get_rate(&m1, *argv) < 0) {
298			explain1("m1");
299			return -1;
300		}
301		NEXT_ARG();
302	}
303
304	if (matches(*argv, "d") == 0) {
305		NEXT_ARG();
306		if (get_usecs(&d, *argv) < 0) {
307			explain1("d");
308			return -1;
309		}
310		NEXT_ARG();
311	}
312
313	if (matches(*argv, "m2") == 0) {
314		NEXT_ARG();
315		if (get_rate(&m2, *argv) < 0) {
316			explain1("m2");
317			return -1;
318		}
319	} else
320		return -1;
321
322	sc->m1 = m1;
323	sc->d  = d;
324	sc->m2 = m2;
325
326	*argvp = argv;
327	*argcp = argc;
328	return 0;
329}
330
331static int
332hfsc_get_sc2(int *argcp, char ***argvp, struct tc_service_curve *sc)
333{
334	char **argv = *argvp;
335	int argc = *argcp;
336	unsigned int umax = 0, dmax = 0, rate = 0;
337
338	if (matches(*argv, "umax") == 0) {
339		NEXT_ARG();
340		if (get_size(&umax, *argv) < 0) {
341			explain1("umax");
342			return -1;
343		}
344		NEXT_ARG();
345	}
346
347	if (matches(*argv, "dmax") == 0) {
348		NEXT_ARG();
349		if (get_usecs(&dmax, *argv) < 0) {
350			explain1("dmax");
351			return -1;
352		}
353		NEXT_ARG();
354	}
355
356	if (matches(*argv, "rate") == 0) {
357		NEXT_ARG();
358		if (get_rate(&rate, *argv) < 0) {
359			explain1("rate");
360			return -1;
361		}
362	} else
363		return -1;
364
365	if (umax != 0 && dmax == 0) {
366		fprintf(stderr, "HFSC: umax given but dmax is zero.\n");
367		return -1;
368	}
369
370	if (dmax != 0 && ceil(umax * 1000000.0 / dmax) > rate) {
371		/*
372		 * concave curve, slope of first segment is umax/dmax,
373		 * intersection is at dmax
374		 */
375		sc->m1 = ceil(umax * 1000000.0 / dmax); /* in bps */
376		sc->d  = dmax;
377		sc->m2 = rate;
378	} else {
379		/*
380		 * convex curve, slope of first segment is 0, intersection
381		 * is at dmax - umax / rate
382		 */
383		sc->m1 = 0;
384		sc->d  = ceil(dmax - umax * 1000000.0 / rate); /* in usec */
385		sc->m2 = rate;
386	}
387
388	*argvp = argv;
389	*argcp = argc;
390	return 0;
391}
392
393static int
394hfsc_get_sc(int *argcp, char ***argvp, struct tc_service_curve *sc)
395{
396	if (hfsc_get_sc1(argcp, argvp, sc) < 0 &&
397	    hfsc_get_sc2(argcp, argvp, sc) < 0)
398		return -1;
399
400	if (sc->m1 == 0 && sc->m2 == 0) {
401		fprintf(stderr, "HFSC: Service Curve has two zero slopes\n");
402		return -1;
403	}
404
405	return 0;
406}
407