1 /*
2 * lib/route/tc.c Traffic Control
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation version 2.1
7 * of the License.
8 *
9 * Copyright (c) 2003-2008 Thomas Graf <tgraf@suug.ch>
10 */
11
12 /**
13 * @ingroup rtnl
14 * @defgroup tc Traffic Control
15 * @brief
16 * @{
17 */
18
19 #include <netlink-local.h>
20 #include <netlink-tc.h>
21 #include <netlink/netlink.h>
22 #include <netlink/utils.h>
23 #include <netlink/route/rtnl.h>
24 #include <netlink/route/link.h>
25 #include <netlink/route/tc.h>
26
27 /** @cond SKIP */
28
29 static struct nla_policy tc_policy[TCA_MAX+1] = {
30 [TCA_KIND] = { .type = NLA_STRING,
31 .maxlen = TCKINDSIZ },
32 [TCA_STATS] = { .minlen = sizeof(struct tc_stats) },
33 [TCA_STATS2] = { .type = NLA_NESTED },
34 };
35
tca_parse(struct nlattr ** tb,int maxattr,struct rtnl_tca * g,struct nla_policy * policy)36 int tca_parse(struct nlattr **tb, int maxattr, struct rtnl_tca *g,
37 struct nla_policy *policy)
38 {
39
40 if (g->ce_mask & TCA_ATTR_OPTS)
41 return nla_parse(tb, maxattr,
42 (struct nlattr *) g->tc_opts->d_data,
43 g->tc_opts->d_size, policy);
44 else {
45 /* Ugly but tb[] must be in a defined state even if no
46 * attributes can be found. */
47 memset(tb, 0, sizeof(struct nlattr *) * (maxattr + 1));
48 return 0;
49 }
50 }
51
52 static struct nla_policy tc_stats2_policy[TCA_STATS_MAX+1] = {
53 [TCA_STATS_BASIC] = { .minlen = sizeof(struct gnet_stats_basic) },
54 [TCA_STATS_RATE_EST] = { .minlen = sizeof(struct gnet_stats_rate_est) },
55 [TCA_STATS_QUEUE] = { .minlen = sizeof(struct gnet_stats_queue) },
56 };
57
tca_msg_parser(struct nlmsghdr * n,struct rtnl_tca * g)58 int tca_msg_parser(struct nlmsghdr *n, struct rtnl_tca *g)
59 {
60 struct nlattr *tb[TCA_MAX + 1];
61 struct tcmsg *tm;
62 int err;
63
64 err = nlmsg_parse(n, sizeof(*tm), tb, TCA_MAX, tc_policy);
65 if (err < 0)
66 return err;
67
68 if (tb[TCA_KIND] == NULL)
69 return -NLE_MISSING_ATTR;
70
71 nla_strlcpy(g->tc_kind, tb[TCA_KIND], TCKINDSIZ);
72
73 tm = nlmsg_data(n);
74 g->tc_family = tm->tcm_family;
75 g->tc_ifindex = tm->tcm_ifindex;
76 g->tc_handle = tm->tcm_handle;
77 g->tc_parent = tm->tcm_parent;
78 g->tc_info = tm->tcm_info;
79
80 g->ce_mask = (TCA_ATTR_FAMILY | TCA_ATTR_IFINDEX | TCA_ATTR_HANDLE |
81 TCA_ATTR_PARENT | TCA_ATTR_INFO | TCA_ATTR_KIND);
82
83 if (tb[TCA_OPTIONS]) {
84 g->tc_opts = nl_data_alloc_attr(tb[TCA_OPTIONS]);
85 if (!g->tc_opts)
86 return -NLE_NOMEM;
87 g->ce_mask |= TCA_ATTR_OPTS;
88 }
89
90
91 if (tb[TCA_STATS2]) {
92 struct nlattr *tbs[TCA_STATS_MAX + 1];
93
94 err = nla_parse_nested(tbs, TCA_STATS_MAX, tb[TCA_STATS2],
95 tc_stats2_policy);
96 if (err < 0)
97 return err;
98
99 if (tbs[TCA_STATS_BASIC]) {
100 struct gnet_stats_basic *bs;
101
102 bs = nla_data(tbs[TCA_STATS_BASIC]);
103 g->tc_stats[RTNL_TC_BYTES] = bs->bytes;
104 g->tc_stats[RTNL_TC_PACKETS] = bs->packets;
105 }
106
107 if (tbs[TCA_STATS_RATE_EST]) {
108 struct gnet_stats_rate_est *re;
109
110 re = nla_data(tbs[TCA_STATS_RATE_EST]);
111 g->tc_stats[RTNL_TC_RATE_BPS] = re->bps;
112 g->tc_stats[RTNL_TC_RATE_PPS] = re->pps;
113 }
114
115 if (tbs[TCA_STATS_QUEUE]) {
116 struct gnet_stats_queue *q;
117
118 q = nla_data(tbs[TCA_STATS_QUEUE]);
119 g->tc_stats[RTNL_TC_QLEN] = q->qlen;
120 g->tc_stats[RTNL_TC_BACKLOG] = q->backlog;
121 g->tc_stats[RTNL_TC_DROPS] = q->drops;
122 g->tc_stats[RTNL_TC_REQUEUES] = q->requeues;
123 g->tc_stats[RTNL_TC_OVERLIMITS] = q->overlimits;
124 }
125
126 g->ce_mask |= TCA_ATTR_STATS;
127
128 if (tbs[TCA_STATS_APP]) {
129 g->tc_xstats = nl_data_alloc_attr(tbs[TCA_STATS_APP]);
130 if (g->tc_xstats == NULL)
131 return -NLE_NOMEM;
132 } else
133 goto compat_xstats;
134 } else {
135 if (tb[TCA_STATS]) {
136 struct tc_stats *st = nla_data(tb[TCA_STATS]);
137
138 g->tc_stats[RTNL_TC_BYTES] = st->bytes;
139 g->tc_stats[RTNL_TC_PACKETS] = st->packets;
140 g->tc_stats[RTNL_TC_RATE_BPS] = st->bps;
141 g->tc_stats[RTNL_TC_RATE_PPS] = st->pps;
142 g->tc_stats[RTNL_TC_QLEN] = st->qlen;
143 g->tc_stats[RTNL_TC_BACKLOG] = st->backlog;
144 g->tc_stats[RTNL_TC_DROPS] = st->drops;
145 g->tc_stats[RTNL_TC_OVERLIMITS] = st->overlimits;
146
147 g->ce_mask |= TCA_ATTR_STATS;
148 }
149
150 compat_xstats:
151 if (tb[TCA_XSTATS]) {
152 g->tc_xstats = nl_data_alloc_attr(tb[TCA_XSTATS]);
153 if (g->tc_xstats == NULL)
154 return -NLE_NOMEM;
155 g->ce_mask |= TCA_ATTR_XSTATS;
156 }
157 }
158
159
160 return 0;
161 }
162
tca_free_data(struct rtnl_tca * tca)163 void tca_free_data(struct rtnl_tca *tca)
164 {
165 nl_data_free(tca->tc_opts);
166 nl_data_free(tca->tc_xstats);
167 }
168
tca_clone(struct rtnl_tca * dst,struct rtnl_tca * src)169 int tca_clone(struct rtnl_tca *dst, struct rtnl_tca *src)
170 {
171 if (src->tc_opts) {
172 dst->tc_opts = nl_data_clone(src->tc_opts);
173 if (!dst->tc_opts)
174 return -NLE_NOMEM;
175 }
176
177 if (src->tc_xstats) {
178 dst->tc_xstats = nl_data_clone(src->tc_xstats);
179 if (!dst->tc_xstats)
180 return -NLE_NOMEM;
181 }
182
183 return 0;
184 }
185
tca_dump_line(struct rtnl_tca * g,const char * type,struct nl_dump_params * p)186 void tca_dump_line(struct rtnl_tca *g, const char *type,
187 struct nl_dump_params *p)
188 {
189 char handle[32], parent[32];
190 struct nl_cache *link_cache;
191
192 link_cache = nl_cache_mngt_require("route/link");
193
194 nl_dump_line(p, "%s %s ", g->tc_kind, type);
195
196 if (link_cache) {
197 char buf[32];
198 nl_dump(p, "dev %s ",
199 rtnl_link_i2name(link_cache, g->tc_ifindex,
200 buf, sizeof(buf)));
201 } else
202 nl_dump(p, "dev %u ", g->tc_ifindex);
203
204 nl_dump(p, "handle %s parent %s",
205 rtnl_tc_handle2str(g->tc_handle, handle, sizeof(handle)),
206 rtnl_tc_handle2str(g->tc_parent, parent, sizeof(parent)));
207 }
208
tca_dump_details(struct rtnl_tca * g,struct nl_dump_params * p)209 void tca_dump_details(struct rtnl_tca *g, struct nl_dump_params *p)
210 {
211 nl_dump_line(p, " ");
212 }
213
tca_dump_stats(struct rtnl_tca * g,struct nl_dump_params * p)214 void tca_dump_stats(struct rtnl_tca *g, struct nl_dump_params *p)
215 {
216 char *unit, fmt[64];
217 float res;
218 strcpy(fmt, " %7.2f %s %10u %10u %10u %10u %10u\n");
219
220 nl_dump_line(p,
221 " Stats: bytes packets drops overlimits" \
222 " qlen backlog\n");
223
224 res = nl_cancel_down_bytes(g->tc_stats[RTNL_TC_BYTES], &unit);
225 if (*unit == 'B')
226 fmt[11] = '9';
227
228 nl_dump_line(p, fmt, res, unit,
229 g->tc_stats[RTNL_TC_PACKETS],
230 g->tc_stats[RTNL_TC_DROPS],
231 g->tc_stats[RTNL_TC_OVERLIMITS],
232 g->tc_stats[RTNL_TC_QLEN],
233 g->tc_stats[RTNL_TC_BACKLOG]);
234
235 res = nl_cancel_down_bytes(g->tc_stats[RTNL_TC_RATE_BPS], &unit);
236
237 strcpy(fmt, " %7.2f %s/s%9u pps");
238
239 if (*unit == 'B')
240 fmt[11] = '9';
241
242 nl_dump_line(p, fmt, res, unit, g->tc_stats[RTNL_TC_RATE_PPS]);
243 }
244
tca_compare(struct nl_object * _a,struct nl_object * _b,uint32_t attrs,int flags)245 int tca_compare(struct nl_object *_a, struct nl_object *_b,
246 uint32_t attrs, int flags)
247 {
248 struct rtnl_tca *a = (struct rtnl_tca *) _a;
249 struct rtnl_tca *b = (struct rtnl_tca *) _b;
250 int diff = 0;
251
252 #define TC_DIFF(ATTR, EXPR) ATTR_DIFF(attrs, TCA_ATTR_##ATTR, a, b, EXPR)
253
254 diff |= TC_DIFF(HANDLE, a->tc_handle != b->tc_handle);
255 diff |= TC_DIFF(PARENT, a->tc_parent != b->tc_parent);
256 diff |= TC_DIFF(IFINDEX, a->tc_ifindex != b->tc_ifindex);
257 diff |= TC_DIFF(KIND, strcmp(a->tc_kind, b->tc_kind));
258
259 #undef TC_DIFF
260
261 return diff;
262 }
263
tca_set_ifindex(struct rtnl_tca * t,int ifindex)264 void tca_set_ifindex(struct rtnl_tca *t, int ifindex)
265 {
266 t->tc_ifindex = ifindex;
267 t->ce_mask |= TCA_ATTR_IFINDEX;
268 }
269
tca_get_ifindex(struct rtnl_tca * t)270 int tca_get_ifindex(struct rtnl_tca *t)
271 {
272 return t->tc_ifindex;
273 }
274
tca_set_handle(struct rtnl_tca * t,uint32_t handle)275 void tca_set_handle(struct rtnl_tca *t, uint32_t handle)
276 {
277 t->tc_handle = handle;
278 t->ce_mask |= TCA_ATTR_HANDLE;
279 }
280
tca_get_handle(struct rtnl_tca * t)281 uint32_t tca_get_handle(struct rtnl_tca *t)
282 {
283 if (t->ce_mask & TCA_ATTR_HANDLE)
284 return t->tc_handle;
285 else
286 return 0;
287 }
288
tca_set_parent(struct rtnl_tca * t,uint32_t parent)289 void tca_set_parent(struct rtnl_tca *t, uint32_t parent)
290 {
291 t->tc_parent = parent;
292 t->ce_mask |= TCA_ATTR_PARENT;
293 }
294
tca_get_parent(struct rtnl_tca * t)295 uint32_t tca_get_parent(struct rtnl_tca *t)
296 {
297 if (t->ce_mask & TCA_ATTR_PARENT)
298 return t->tc_parent;
299 else
300 return 0;
301 }
302
tca_set_kind(struct rtnl_tca * t,const char * kind)303 void tca_set_kind(struct rtnl_tca *t, const char *kind)
304 {
305 strncpy(t->tc_kind, kind, sizeof(t->tc_kind) - 1);
306 t->ce_mask |= TCA_ATTR_KIND;
307 }
308
tca_get_kind(struct rtnl_tca * t)309 char *tca_get_kind(struct rtnl_tca *t)
310 {
311 if (t->ce_mask & TCA_ATTR_KIND)
312 return t->tc_kind;
313 else
314 return NULL;
315 }
316
tca_get_stat(struct rtnl_tca * t,int id)317 uint64_t tca_get_stat(struct rtnl_tca *t, int id)
318 {
319 if (id < 0 || id > RTNL_TC_STATS_MAX)
320 return 0;
321
322 return t->tc_stats[id];
323 }
324
tca_build_msg(struct rtnl_tca * tca,int type,int flags,struct nl_msg ** result)325 int tca_build_msg(struct rtnl_tca *tca, int type, int flags,
326 struct nl_msg **result)
327 {
328 struct nl_msg *msg;
329 struct tcmsg tchdr = {
330 .tcm_family = AF_UNSPEC,
331 .tcm_ifindex = tca->tc_ifindex,
332 .tcm_handle = tca->tc_handle,
333 .tcm_parent = tca->tc_parent,
334 };
335
336 msg = nlmsg_alloc_simple(type, flags);
337 if (!msg)
338 return -NLE_NOMEM;
339
340 if (nlmsg_append(msg, &tchdr, sizeof(tchdr), NLMSG_ALIGNTO) < 0)
341 goto nla_put_failure;
342
343 if (tca->ce_mask & TCA_ATTR_KIND)
344 NLA_PUT_STRING(msg, TCA_KIND, tca->tc_kind);
345
346 *result = msg;
347 return 0;
348
349 nla_put_failure:
350 nlmsg_free(msg);
351 return -NLE_MSGSIZE;
352 }
353
354 /** @endcond */
355
356 /**
357 * @name Utilities
358 * @{
359 */
360
361 /**
362 * Calculate time required to transmit buffer at a specific rate
363 * @arg bufsize Size of buffer to be transmited in bytes.
364 * @arg rate Transmit rate in bytes per second.
365 *
366 * Calculates the number of micro seconds required to transmit a
367 * specific buffer at a specific transmit rate.
368 *
369 * @f[
370 * txtime=\frac{bufsize}{rate}10^6
371 * @f]
372 *
373 * @return Required transmit time in micro seconds.
374 */
rtnl_tc_calc_txtime(int bufsize,int rate)375 int rtnl_tc_calc_txtime(int bufsize, int rate)
376 {
377 double tx_time_secs;
378
379 tx_time_secs = (double) bufsize / (double) rate;
380
381 return tx_time_secs * 1000000.;
382 }
383
384 /**
385 * Calculate buffer size able to transmit in a specific time and rate.
386 * @arg txtime Available transmit time in micro seconds.
387 * @arg rate Transmit rate in bytes per second.
388 *
389 * Calculates the size of the buffer that can be transmitted in a
390 * specific time period at a specific transmit rate.
391 *
392 * @f[
393 * bufsize=\frac{{txtime} \times {rate}}{10^6}
394 * @f]
395 *
396 * @return Size of buffer in bytes.
397 */
rtnl_tc_calc_bufsize(int txtime,int rate)398 int rtnl_tc_calc_bufsize(int txtime, int rate)
399 {
400 double bufsize;
401
402 bufsize = (double) txtime * (double) rate;
403
404 return bufsize / 1000000.;
405 }
406
407 /**
408 * Calculate the binary logarithm for a specific cell size
409 * @arg cell_size Size of cell, must be a power of two.
410 * @return Binary logirhtm of cell size or a negative error code.
411 */
rtnl_tc_calc_cell_log(int cell_size)412 int rtnl_tc_calc_cell_log(int cell_size)
413 {
414 int i;
415
416 for (i = 0; i < 32; i++)
417 if ((1 << i) == cell_size)
418 return i;
419
420 return -NLE_INVAL;
421 }
422
423
424 /** @} */
425
426 /**
427 * @name Rate Tables
428 * @{
429 */
430
431 /**
432 * Compute a transmission time lookup table
433 * @arg dst Destination buffer of RTNL_TC_RTABLE_SIZE uint32_t[].
434 * @arg mpu Minimal size of a packet at all times.
435 * @arg overhead Overhead to be added to each packet.
436 * @arg cell Size of cell, i.e. size of step between entries in bytes.
437 * @arg rate Rate in bytes per second.
438 *
439 * Computes a table of RTNL_TC_RTABLE_SIZE entries specyfing the
440 * transmission times for various packet sizes, e.g. the transmission
441 * time for a packet of size \c pktsize could be looked up:
442 * @code
443 * txtime = table[pktsize >> log2(cell)];
444 * @endcode
445 */
rtnl_tc_build_rate_table(uint32_t * dst,uint8_t mpu,uint8_t overhead,int cell,int rate)446 int rtnl_tc_build_rate_table(uint32_t *dst, uint8_t mpu, uint8_t overhead,
447 int cell, int rate)
448 {
449 int i, size, cell_log;
450
451 cell_log = rtnl_tc_calc_cell_log(cell);
452 if (cell_log < 0)
453 return cell_log;
454
455 for (i = 0; i < RTNL_TC_RTABLE_SIZE; i++) {
456 size = (i << cell_log) + overhead;
457 if (size < mpu)
458 size = mpu;
459
460 dst[i] = rtnl_tc_calc_txtime(size, rate);
461 }
462
463 return 0;
464 }
465
466 /** @} */
467
468 /**
469 * @name Traffic Control Handle Translations
470 * @{
471 */
472
473 /**
474 * Convert a traffic control handle to a character string (Reentrant).
475 * @arg handle traffic control handle
476 * @arg buf destination buffer
477 * @arg len buffer length
478 *
479 * Converts a tarffic control handle to a character string in the
480 * form of \c MAJ:MIN and stores it in the specified destination buffer.
481 *
482 * @return The destination buffer or the type encoded in hexidecimal
483 * form if no match was found.
484 */
rtnl_tc_handle2str(uint32_t handle,char * buf,size_t len)485 char * rtnl_tc_handle2str(uint32_t handle, char *buf, size_t len)
486 {
487 if (TC_H_ROOT == handle)
488 snprintf(buf, len, "root");
489 else if (TC_H_UNSPEC == handle)
490 snprintf(buf, len, "none");
491 else if (0 == TC_H_MAJ(handle))
492 snprintf(buf, len, ":%02x", TC_H_MIN(handle));
493 else if (0 == TC_H_MIN(handle))
494 snprintf(buf, len, "%02x:", TC_H_MAJ(handle) >> 16);
495 else
496 snprintf(buf, len, "%02x:%02x",
497 TC_H_MAJ(handle) >> 16, TC_H_MIN(handle));
498
499 return buf;
500 }
501
502 /**
503 * Convert a charactering strint to a traffic control handle
504 * @arg name traffic control handle as character string
505 * @arg res destination buffer
506 *
507 * Converts the provided character string specifying a traffic
508 * control handle to the corresponding numeric value.
509 *
510 * The handle must be provided in one of the following formats:
511 * - root
512 * - none
513 * - XXXX:
514 * - :YYYY
515 * - XXXX:YYYY
516 * - XXXXYYYY
517 *
518 * @return 0 on success or a negative error code
519 */
rtnl_tc_str2handle(const char * name,uint32_t * res)520 int rtnl_tc_str2handle(const char *name, uint32_t *res)
521 {
522 char *colon, *end;
523 uint32_t h;
524
525 if (!strcasecmp(name, "root")) {
526 *res = TC_H_ROOT;
527 return 0;
528 }
529
530 if (!strcasecmp(name, "none")) {
531 *res = TC_H_UNSPEC;
532 return 0;
533 }
534
535 h = strtoul(name, &colon, 16);
536
537 if (colon == name) {
538 /* :YYYY */
539 h = 0;
540 if (':' != *colon)
541 return -NLE_INVAL;
542 }
543
544 if (':' == *colon) {
545 /* check if we would lose bits */
546 if (TC_H_MAJ(h))
547 return -NLE_RANGE;
548 h <<= 16;
549
550 if ('\0' == colon[1]) {
551 /* XXXX: */
552 *res = h;
553 } else {
554 /* XXXX:YYYY */
555 uint32_t l = strtoul(colon+1, &end, 16);
556
557 /* check if we overlap with major part */
558 if (TC_H_MAJ(l))
559 return -NLE_RANGE;
560
561 if ('\0' != *end)
562 return -NLE_INVAL;
563
564 *res = (h | l);
565 }
566 } else if ('\0' == *colon) {
567 /* XXXXYYYY */
568 *res = h;
569 } else
570 return -NLE_INVAL;
571
572 return 0;
573 }
574
575 /** @} */
576
577 /** @} */
578