tc.c revision b4fbe1d34d6f54045b5c6236d86aacd4340ec83d
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 29static 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 36int 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 52static 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 58int 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 150compat_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 163void tca_free_data(struct rtnl_tca *tca) 164{ 165 nl_data_free(tca->tc_opts); 166 nl_data_free(tca->tc_xstats); 167} 168 169int 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 186int tca_dump_brief(struct rtnl_tca *g, const char *type, 187 struct nl_dump_params *p, int line) 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 dp_dump(p, "%s %s ", g->tc_kind, type); 195 196 if (link_cache) { 197 char buf[32]; 198 dp_dump(p, "dev %s ", 199 rtnl_link_i2name(link_cache, g->tc_ifindex, 200 buf, sizeof(buf))); 201 } else 202 dp_dump(p, "dev %u ", g->tc_ifindex); 203 204 dp_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 return 1; 209} 210 211int tca_dump_full(struct rtnl_tca *g, struct nl_dump_params *p, int line) 212{ 213 dp_dump_line(p, line++, " "); 214 return line; 215} 216 217int tca_dump_stats(struct rtnl_tca *g, struct nl_dump_params *p, int line) 218{ 219 char *unit, fmt[64]; 220 float res; 221 strcpy(fmt, " %7.2f %s %10u %10u %10u %10u %10u\n"); 222 223 dp_dump_line(p, line++, 224 " Stats: bytes packets drops overlimits" \ 225 " qlen backlog\n"); 226 227 res = nl_cancel_down_bytes(g->tc_stats[RTNL_TC_BYTES], &unit); 228 if (*unit == 'B') 229 fmt[11] = '9'; 230 231 dp_dump_line(p, line++, fmt, res, unit, 232 g->tc_stats[RTNL_TC_PACKETS], 233 g->tc_stats[RTNL_TC_DROPS], 234 g->tc_stats[RTNL_TC_OVERLIMITS], 235 g->tc_stats[RTNL_TC_QLEN], 236 g->tc_stats[RTNL_TC_BACKLOG]); 237 238 res = nl_cancel_down_bytes(g->tc_stats[RTNL_TC_RATE_BPS], &unit); 239 240 strcpy(fmt, " %7.2f %s/s%9u pps"); 241 242 if (*unit == 'B') 243 fmt[11] = '9'; 244 245 dp_dump_line(p, line++, fmt, res, unit, g->tc_stats[RTNL_TC_RATE_PPS]); 246 247 return line; 248} 249 250int tca_compare(struct nl_object *_a, struct nl_object *_b, 251 uint32_t attrs, int flags) 252{ 253 struct rtnl_tca *a = (struct rtnl_tca *) _a; 254 struct rtnl_tca *b = (struct rtnl_tca *) _b; 255 int diff = 0; 256 257#define TC_DIFF(ATTR, EXPR) ATTR_DIFF(attrs, TCA_ATTR_##ATTR, a, b, EXPR) 258 259 diff |= TC_DIFF(HANDLE, a->tc_handle != b->tc_handle); 260 diff |= TC_DIFF(PARENT, a->tc_parent != b->tc_parent); 261 diff |= TC_DIFF(IFINDEX, a->tc_ifindex != b->tc_ifindex); 262 diff |= TC_DIFF(KIND, strcmp(a->tc_kind, b->tc_kind)); 263 264#undef TC_DIFF 265 266 return diff; 267} 268 269void tca_set_ifindex(struct rtnl_tca *t, int ifindex) 270{ 271 t->tc_ifindex = ifindex; 272 t->ce_mask |= TCA_ATTR_IFINDEX; 273} 274 275int tca_get_ifindex(struct rtnl_tca *t) 276{ 277 return t->tc_ifindex; 278} 279 280void tca_set_handle(struct rtnl_tca *t, uint32_t handle) 281{ 282 t->tc_handle = handle; 283 t->ce_mask |= TCA_ATTR_HANDLE; 284} 285 286uint32_t tca_get_handle(struct rtnl_tca *t) 287{ 288 if (t->ce_mask & TCA_ATTR_HANDLE) 289 return t->tc_handle; 290 else 291 return 0; 292} 293 294void tca_set_parent(struct rtnl_tca *t, uint32_t parent) 295{ 296 t->tc_parent = parent; 297 t->ce_mask |= TCA_ATTR_PARENT; 298} 299 300uint32_t tca_get_parent(struct rtnl_tca *t) 301{ 302 if (t->ce_mask & TCA_ATTR_PARENT) 303 return t->tc_parent; 304 else 305 return 0; 306} 307 308void tca_set_kind(struct rtnl_tca *t, const char *kind) 309{ 310 strncpy(t->tc_kind, kind, sizeof(t->tc_kind) - 1); 311 t->ce_mask |= TCA_ATTR_KIND; 312} 313 314char *tca_get_kind(struct rtnl_tca *t) 315{ 316 if (t->ce_mask & TCA_ATTR_KIND) 317 return t->tc_kind; 318 else 319 return NULL; 320} 321 322uint64_t tca_get_stat(struct rtnl_tca *t, int id) 323{ 324 if (id < 0 || id > RTNL_TC_STATS_MAX) 325 return 0; 326 327 return t->tc_stats[id]; 328} 329 330int tca_build_msg(struct rtnl_tca *tca, int type, int flags, 331 struct nl_msg **result) 332{ 333 struct nl_msg *msg; 334 struct tcmsg tchdr = { 335 .tcm_family = AF_UNSPEC, 336 .tcm_ifindex = tca->tc_ifindex, 337 .tcm_handle = tca->tc_handle, 338 .tcm_parent = tca->tc_parent, 339 }; 340 341 msg = nlmsg_alloc_simple(type, flags); 342 if (!msg) 343 return -NLE_NOMEM; 344 345 if (nlmsg_append(msg, &tchdr, sizeof(tchdr), NLMSG_ALIGNTO) < 0) 346 goto nla_put_failure; 347 348 if (tca->ce_mask & TCA_ATTR_KIND) 349 NLA_PUT_STRING(msg, TCA_KIND, tca->tc_kind); 350 351 *result = msg; 352 return 0; 353 354nla_put_failure: 355 nlmsg_free(msg); 356 return -NLE_MSGSIZE; 357} 358 359/** @endcond */ 360 361/** 362 * @name Utilities 363 * @{ 364 */ 365 366/** 367 * Calculate time required to transmit buffer at a specific rate 368 * @arg bufsize Size of buffer to be transmited in bytes. 369 * @arg rate Transmit rate in bytes per second. 370 * 371 * Calculates the number of micro seconds required to transmit a 372 * specific buffer at a specific transmit rate. 373 * 374 * @f[ 375 * txtime=\frac{bufsize}{rate}10^6 376 * @f] 377 * 378 * @return Required transmit time in micro seconds. 379 */ 380int rtnl_tc_calc_txtime(int bufsize, int rate) 381{ 382 double tx_time_secs; 383 384 tx_time_secs = (double) bufsize / (double) rate; 385 386 return tx_time_secs * 1000000.; 387} 388 389/** 390 * Calculate buffer size able to transmit in a specific time and rate. 391 * @arg txtime Available transmit time in micro seconds. 392 * @arg rate Transmit rate in bytes per second. 393 * 394 * Calculates the size of the buffer that can be transmitted in a 395 * specific time period at a specific transmit rate. 396 * 397 * @f[ 398 * bufsize=\frac{{txtime} \times {rate}}{10^6} 399 * @f] 400 * 401 * @return Size of buffer in bytes. 402 */ 403int rtnl_tc_calc_bufsize(int txtime, int rate) 404{ 405 double bufsize; 406 407 bufsize = (double) txtime * (double) rate; 408 409 return bufsize / 1000000.; 410} 411 412/** 413 * Calculate the binary logarithm for a specific cell size 414 * @arg cell_size Size of cell, must be a power of two. 415 * @return Binary logirhtm of cell size or a negative error code. 416 */ 417int rtnl_tc_calc_cell_log(int cell_size) 418{ 419 int i; 420 421 for (i = 0; i < 32; i++) 422 if ((1 << i) == cell_size) 423 return i; 424 425 return -NLE_INVAL; 426} 427 428 429/** @} */ 430 431/** 432 * @name Rate Tables 433 * @{ 434 */ 435 436/** 437 * Compute a transmission time lookup table 438 * @arg dst Destination buffer of RTNL_TC_RTABLE_SIZE uint32_t[]. 439 * @arg mpu Minimal size of a packet at all times. 440 * @arg overhead Overhead to be added to each packet. 441 * @arg cell Size of cell, i.e. size of step between entries in bytes. 442 * @arg rate Rate in bytes per second. 443 * 444 * Computes a table of RTNL_TC_RTABLE_SIZE entries specyfing the 445 * transmission times for various packet sizes, e.g. the transmission 446 * time for a packet of size \c pktsize could be looked up: 447 * @code 448 * txtime = table[pktsize >> log2(cell)]; 449 * @endcode 450 */ 451int rtnl_tc_build_rate_table(uint32_t *dst, uint8_t mpu, uint8_t overhead, 452 int cell, int rate) 453{ 454 int i, size, cell_log; 455 456 cell_log = rtnl_tc_calc_cell_log(cell); 457 if (cell_log < 0) 458 return cell_log; 459 460 for (i = 0; i < RTNL_TC_RTABLE_SIZE; i++) { 461 size = (i << cell_log) + overhead; 462 if (size < mpu) 463 size = mpu; 464 465 dst[i] = rtnl_tc_calc_txtime(size, rate); 466 } 467 468 return 0; 469} 470 471/** @} */ 472 473/** 474 * @name Traffic Control Handle Translations 475 * @{ 476 */ 477 478/** 479 * Convert a traffic control handle to a character string (Reentrant). 480 * @arg handle traffic control handle 481 * @arg buf destination buffer 482 * @arg len buffer length 483 * 484 * Converts a tarffic control handle to a character string in the 485 * form of \c MAJ:MIN and stores it in the specified destination buffer. 486 * 487 * @return The destination buffer or the type encoded in hexidecimal 488 * form if no match was found. 489 */ 490char * rtnl_tc_handle2str(uint32_t handle, char *buf, size_t len) 491{ 492 if (TC_H_ROOT == handle) 493 snprintf(buf, len, "root"); 494 else if (TC_H_UNSPEC == handle) 495 snprintf(buf, len, "none"); 496 else if (0 == TC_H_MAJ(handle)) 497 snprintf(buf, len, ":%02x", TC_H_MIN(handle)); 498 else if (0 == TC_H_MIN(handle)) 499 snprintf(buf, len, "%02x:", TC_H_MAJ(handle) >> 16); 500 else 501 snprintf(buf, len, "%02x:%02x", 502 TC_H_MAJ(handle) >> 16, TC_H_MIN(handle)); 503 504 return buf; 505} 506 507/** 508 * Convert a charactering strint to a traffic control handle 509 * @arg name traffic control handle as character string 510 * @arg res destination buffer 511 * 512 * Converts the provided character string specifying a traffic 513 * control handle to the corresponding numeric value. 514 * 515 * The handle must be provided in one of the following formats: 516 * - root 517 * - none 518 * - XXXX: 519 * - :YYYY 520 * - XXXX:YYYY 521 * - XXXXYYYY 522 * 523 * @return 0 on success or a negative error code 524 */ 525int rtnl_tc_str2handle(const char *name, uint32_t *res) 526{ 527 char *colon, *end; 528 uint32_t h; 529 530 if (!strcasecmp(name, "root")) { 531 *res = TC_H_ROOT; 532 return 0; 533 } 534 535 if (!strcasecmp(name, "none")) { 536 *res = TC_H_UNSPEC; 537 return 0; 538 } 539 540 h = strtoul(name, &colon, 16); 541 542 if (colon == name) { 543 /* :YYYY */ 544 h = 0; 545 if (':' != *colon) 546 return -NLE_INVAL; 547 } 548 549 if (':' == *colon) { 550 /* check if we would lose bits */ 551 if (TC_H_MAJ(h)) 552 return -NLE_RANGE; 553 h <<= 16; 554 555 if ('\0' == colon[1]) { 556 /* XXXX: */ 557 *res = h; 558 } else { 559 /* XXXX:YYYY */ 560 uint32_t l = strtoul(colon+1, &end, 16); 561 562 /* check if we overlap with major part */ 563 if (TC_H_MAJ(l)) 564 return -NLE_RANGE; 565 566 if ('\0' != *end) 567 return -NLE_INVAL; 568 569 *res = (h | l); 570 } 571 } else if ('\0' == *colon) { 572 /* XXXXYYYY */ 573 *res = h; 574 } else 575 return -NLE_INVAL; 576 577 return 0; 578} 579 580/** @} */ 581 582/** @} */ 583