tc/q_netem.c

   1 /*
   2  * q_netem.c            NETEM.
   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:     Stephen Hemminger <shemminger@linux-foundation.org>
  10  *
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <math.h>
  16 #include <ctype.h>
  17 #include <unistd.h>
  18 #include <syslog.h>
  19 #include <fcntl.h>
  20 #include <sys/socket.h>
  21 #include <netinet/in.h>
  22 #include <arpa/inet.h>
  23 #include <string.h>
  24 #include <errno.h>
  25
  26 #include "utils.h"
  27 #include "tc_util.h"
  28 #include "tc_common.h"
  29
  30 static void explain(void)
  31 {
  32         fprintf(stderr,
  33 "Usage: ... netem [ limit PACKETS ] \n" \
  34 "                 [ delay TIME [ JITTER [CORRELATION]]]\n" \
  35 "                 [ distribution {uniform|normal|pareto|paretonormal} ]\n" \
  36 "                 [ corrupt PERCENT [CORRELATION]] \n" \
  37 "                 [ duplicate PERCENT [CORRELATION]]\n" \
  38 "                 [ loss random PERCENT [CORRELATION]]\n" \
  39 "                 [ loss state P13 [P31 [P32 [P23 P14]]]\n" \
  40 "                 [ loss gemodel PERCENT [R [1-H [1-K]]]\n" \
  41 "                 [ ecn ]\n" \
  42 "                 [ reorder PRECENT [CORRELATION] [ gap DISTANCE ]]\n" \
  43 "                 [ rate RATE [PACKETOVERHEAD] [CELLSIZE] [CELLOVERHEAD]]\n");
  44 }
  45
  46 static void explain1(const char *arg)
  47 {
  48         fprintf(stderr, "Illegal \"%s\"\n", arg);
  49 }
  50
  51 /* Upper bound on size of distribution
  52  *  really (TCA_BUF_MAX - other headers) / sizeof (__s16)
  53  */
  54 #define MAX_DIST        (16*1024)
  55
  56 static const double max_percent_value = 0xffffffff;
  57
  58 /* scaled value used to percent of maximum. */
  59 static void set_percent(__u32 *percent, double per)
  60 {
  61         *percent = (unsigned) rint(per * max_percent_value);
  62 }
  63
  64
  65 /* Parse either a fraction '.3' or percent '30%
  66  * return: 0 = ok, -1 = error, 1 = out of range
  67  */
  68 static int parse_percent(double *val, const char *str)
  69 {
  70         char *p;
  71
  72         *val = strtod(str, &p) / 100.;
  73         if (*p && strcmp(p, "%") )
  74                 return -1;
  75
  76         return 0;
  77 }
  78
  79 static int get_percent(__u32 *percent, const char *str)
  80 {
  81         double per;
  82
  83         if (parse_percent(&per, str))
  84                 return -1;
  85
  86         set_percent(percent, per);
  87         return 0;
  88 }
  89
  90 static void print_percent(char *buf, int len, __u32 per)
  91 {
  92         snprintf(buf, len, "%g%%", 100. * (double) per / max_percent_value);
  93 }
  94
  95 static char * sprint_percent(__u32 per, char *buf)
  96 {
  97         print_percent(buf, SPRINT_BSIZE-1, per);
  98         return buf;
  99 }
 100
 101 /*
 102  * Simplistic file parser for distrbution data.
 103  * Format is:
 104  *      # comment line(s)
 105  *      data0 data1 ...
 106  */
 107 static int get_distribution(const char *type, __s16 *data, int maxdata)
 108 {
 109         FILE *f;
 110         int n;
 111         long x;
 112         size_t len;
 113         char *line = NULL;
 114         char name[128];
 115
 116         snprintf(name, sizeof(name), "%s/%s.dist", get_tc_lib(), type);
 117         if ((f = fopen(name, "r")) == NULL) {
 118                 fprintf(stderr, "No distribution data for %s (%s: %s)\n",
 119                         type, name, strerror(errno));
 120                 return -1;
 121         }
 122
 123         n = 0;
 124         while (getline(&line, &len, f) != -1) {
 125                 char *p, *endp;
 126                 if (*line == '\n' || *line == '#')
 127                         continue;
 128
 129                 for (p = line; ; p = endp) {
 130                         x = strtol(p, &endp, 0);
 131                         if (endp == p)
 132                                 break;
 133
 134                         if (n >= maxdata) {
 135                                 fprintf(stderr, "%s: too much data\n",
 136                                         name);
 137                                 n = -1;
 138                                 goto error;
 139                         }
 140                         data[n++] = x;
 141                 }
 142         }
 143  error:
 144         free(line);
 145         fclose(f);
 146         return n;
 147 }
 148
 149 #define NEXT_IS_NUMBER() (NEXT_ARG_OK() && isdigit(argv[1][0]))
 150 #define NEXT_IS_SIGNED_NUMBER() \
 151         (NEXT_ARG_OK() && (isdigit(argv[1][0]) || argv[1][0] == '-'))
 152
 153 /* Adjust for the fact that psched_ticks aren't always usecs
 154    (based on kernel PSCHED_CLOCK configuration */
 155 static int get_ticks(__u32 *ticks, const char *str)
 156 {
 157         unsigned t;
 158
 159         if(get_time(&t, str))
 160                 return -1;
 161
 162         if (tc_core_time2big(t)) {
 163                 fprintf(stderr, "Illegal %u time (too large)\n", t);
 164                 return -1;
 165         }
 166
 167         *ticks = tc_core_time2tick(t);
 168         return 0;
 169 }
 170
 171 static int netem_parse_opt(struct qdisc_util *qu, int argc, char **argv,
 172                            struct nlmsghdr *n)
 173 {
 174         int dist_size = 0;
 175         struct rtattr *tail;
 176         struct tc_netem_qopt opt = { .limit = 1000 };
 177         struct tc_netem_corr cor;
 178         struct tc_netem_reorder reorder;
 179         struct tc_netem_corrupt corrupt;
 180         struct tc_netem_gimodel gimodel;
 181         struct tc_netem_gemodel gemodel;
 182         struct tc_netem_rate rate;
 183         __s16 *dist_data = NULL;
 184         __u16 loss_type = NETEM_LOSS_UNSPEC;
 185         int present[__TCA_NETEM_MAX];
 186
 187         memset(&cor, 0, sizeof(cor));
 188         memset(&reorder, 0, sizeof(reorder));
 189         memset(&corrupt, 0, sizeof(corrupt));
 190         memset(&rate, 0, sizeof(rate));
 191         memset(present, 0, sizeof(present));
 192
 193         for( ; argc > 0; --argc, ++argv) {
 194                 if (matches(*argv, "limit") == 0) {
 195                         NEXT_ARG();
 196                         if (get_size(&opt.limit, *argv)) {
 197                                 explain1("limit");
 198                                 return -1;
 199                         }
 200                 } else if (matches(*argv, "latency") == 0 ||
 201                            matches(*argv, "delay") == 0) {
 202                         NEXT_ARG();
 203                         if (get_ticks(&opt.latency, *argv)) {
 204                                 explain1("latency");
 205                                 return -1;
 206                         }
 207
 208                         if (NEXT_IS_NUMBER()) {
 209                                 NEXT_ARG();
 210                                 if (get_ticks(&opt.jitter, *argv)) {
 211                                         explain1("latency");
 212                                         return -1;
 213                                 }
 214
 215                                 if (NEXT_IS_NUMBER()) {
 216                                         NEXT_ARG();
 217                                         ++present[TCA_NETEM_CORR];
 218                                         if (get_percent(&cor.delay_corr, *argv)) {
 219                                                 explain1("latency");
 220                                                 return -1;
 221                                         }
 222                                 }
 223                         }
 224                 } else if (matches(*argv, "loss") == 0 ||
 225                            matches(*argv, "drop") == 0) {
 226                         if (opt.loss > 0 || loss_type != NETEM_LOSS_UNSPEC) {
 227                                 explain1("duplicate loss argument\n");
 228                                 return -1;
 229                         }
 230
 231                         NEXT_ARG();
 232                         /* Old (deprecated) random loss model syntax */
 233                         if (isdigit(argv[0][0]))
 234                                 goto random_loss_model;
 235
 236                         if (!strcmp(*argv, "random")) {
 237                                 NEXT_ARG();
 238         random_loss_model:
 239                                 if (get_percent(&opt.loss, *argv)) {
 240                                         explain1("loss percent");
 241                                         return -1;
 242                                 }
 243                                 if (NEXT_IS_NUMBER()) {
 244                                         NEXT_ARG();
 245                                         ++present[TCA_NETEM_CORR];
 246                                         if (get_percent(&cor.loss_corr, *argv)) {
 247                                                 explain1("loss correllation");
 248                                                 return -1;
 249                                         }
 250                                 }
 251                         } else if (!strcmp(*argv, "state")) {
 252                                 double p13;
 253
 254                                 NEXT_ARG();
 255                                 if (parse_percent(&p13, *argv)) {
 256                                         explain1("loss p13");
 257                                         return -1;
 258                                 }
 259
 260                                 /* set defaults */
 261                                 set_percent(&gimodel.p13, p13);
 262                                 set_percent(&gimodel.p31, 1. - p13);
 263                                 set_percent(&gimodel.p32, 0);
 264                                 set_percent(&gimodel.p23, 1.);
 265                                 loss_type = NETEM_LOSS_GI;
 266
 267                                 if (!NEXT_IS_NUMBER())
 268                                         continue;
 269                                 NEXT_ARG();
 270                                 if (get_percent(&gimodel.p31, *argv)) {
 271                                         explain1("loss p31");
 272                                         return -1;
 273                                 }
 274
 275                                 if (!NEXT_IS_NUMBER())
 276                                         continue;
 277                                 NEXT_ARG();
 278                                 if (get_percent(&gimodel.p32, *argv)) {
 279                                         explain1("loss p32");
 280                                         return -1;
 281                                 }
 282
 283                                 if (!NEXT_IS_NUMBER())
 284                                         continue;
 285                                 NEXT_ARG();
 286                                 if (get_percent(&gimodel.p23, *argv)) {
 287                                         explain1("loss p23");
 288                                         return -1;
 289                                 }
 290
 291                         } else if (!strcmp(*argv, "gemodel")) {
 292                                 NEXT_ARG();
 293                                 if (get_percent(&gemodel.p, *argv)) {
 294                                         explain1("loss gemodel p");
 295                                         return -1;
 296                                 }
 297
 298                                 /* set defaults */
 299                                 set_percent(&gemodel.r, 1.);
 300                                 set_percent(&gemodel.h, 0);
 301                                 set_percent(&gemodel.k1, 1.);
 302                                 loss_type = NETEM_LOSS_GE;
 303
 304                                 if (!NEXT_IS_NUMBER())
 305                                         continue;
 306                                 NEXT_ARG();
 307                                 if (get_percent(&gemodel.r, *argv)) {
 308                                         explain1("loss gemodel r");
 309                                         return -1;
 310                                 }
 311
 312                                 if (!NEXT_IS_NUMBER())
 313                                         continue;
 314                                 NEXT_ARG();
 315                                 if (get_percent(&gemodel.h, *argv)) {
 316                                         explain1("loss gemodel h");
 317                                         return -1;
 318                                 }
 319
 320                                 if (!NEXT_IS_NUMBER())
 321                                         continue;
 322                                 NEXT_ARG();
 323                                 if (get_percent(&gemodel.k1, *argv)) {
 324                                         explain1("loss gemodel k");
 325                                         return -1;
 326                                 }
 327                         } else {
 328                                 fprintf(stderr, "Unknown loss parameter: %s\n",
 329                                         *argv);
 330                                 return -1;
 331                         }
 332                 } else if (matches(*argv, "ecn") == 0) {
 333                                 present[TCA_NETEM_ECN] = 1;
 334                 } else if (matches(*argv, "reorder") == 0) {
 335                         NEXT_ARG();
 336                         present[TCA_NETEM_REORDER] = 1;
 337                         if (get_percent(&reorder.probability, *argv)) {
 338                                 explain1("reorder");
 339                                 return -1;
 340                         }
 341                         if (NEXT_IS_NUMBER()) {
 342                                 NEXT_ARG();
 343                                 ++present[TCA_NETEM_CORR];
 344                                 if (get_percent(&reorder.correlation, *argv)) {
 345                                         explain1("reorder");
 346                                         return -1;
 347                                 }
 348                         }
 349                 } else if (matches(*argv, "corrupt") == 0) {
 350                         NEXT_ARG();
 351                         present[TCA_NETEM_CORRUPT] = 1;
 352                         if (get_percent(&corrupt.probability, *argv)) {
 353                                 explain1("corrupt");
 354                                 return -1;
 355                         }
 356                         if (NEXT_IS_NUMBER()) {
 357                                 NEXT_ARG();
 358                                 ++present[TCA_NETEM_CORR];
 359                                 if (get_percent(&corrupt.correlation, *argv)) {
 360                                         explain1("corrupt");
 361                                         return -1;
 362                                 }
 363                         }
 364                 } else if (matches(*argv, "gap") == 0) {
 365                         NEXT_ARG();
 366                         if (get_u32(&opt.gap, *argv, 0)) {
 367                                 explain1("gap");
 368                                 return -1;
 369                         }
 370                 } else if (matches(*argv, "duplicate") == 0) {
 371                         NEXT_ARG();
 372                         if (get_percent(&opt.duplicate, *argv)) {
 373                                 explain1("duplicate");
 374                                 return -1;
 375                         }
 376                         if (NEXT_IS_NUMBER()) {
 377                                 NEXT_ARG();
 378                                 if (get_percent(&cor.dup_corr, *argv)) {
 379                                         explain1("duplicate");
 380                                         return -1;
 381                                 }
 382                         }
 383                 } else if (matches(*argv, "distribution") == 0) {
 384                         NEXT_ARG();
 385                         dist_data = calloc(sizeof(dist_data[0]), MAX_DIST);
 386                         dist_size = get_distribution(*argv, dist_data, MAX_DIST);
 387                         if (dist_size <= 0) {
 388                                 free(dist_data);
 389                                 return -1;
 390                         }
 391                 } else if (matches(*argv, "rate") == 0) {
 392                         ++present[TCA_NETEM_RATE];
 393                         NEXT_ARG();
 394                         if (get_rate(&rate.rate, *argv)) {
 395                                 explain1("rate");
 396                                 return -1;
 397                         }
 398                         if (NEXT_IS_SIGNED_NUMBER()) {
 399                                 NEXT_ARG();
 400                                 if (get_s32(&rate.packet_overhead, *argv, 0)) {
 401                                         explain1("rate");
 402                                         return -1;
 403                                 }
 404                         }
 405                         if (NEXT_IS_NUMBER()) {
 406                                 NEXT_ARG();
 407                                 if (get_u32(&rate.cell_size, *argv, 0)) {
 408                                         explain1("rate");
 409                                         return -1;
 410                                 }
 411                         }
 412                         if (NEXT_IS_SIGNED_NUMBER()) {
 413                                 NEXT_ARG();
 414                                 if (get_s32(&rate.cell_overhead, *argv, 0)) {
 415                                         explain1("rate");
 416                                         return -1;
 417                                 }
 418                         }
 419                 } else if (strcmp(*argv, "help") == 0) {
 420                         explain();
 421                         return -1;
 422                 } else {
 423                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 424                         explain();
 425                         return -1;
 426                 }
 427         }
 428
 429         tail = NLMSG_TAIL(n);
 430
 431         if (reorder.probability) {
 432                 if (opt.latency == 0) {
 433                         fprintf(stderr, "reordering not possible without specifying some delay\n");
 434                         explain();
 435                         return -1;
 436                 }
 437                 if (opt.gap == 0)
 438                         opt.gap = 1;
 439         } else if (opt.gap > 0) {
 440                 fprintf(stderr, "gap specified without reorder probability\n");
 441                 explain();
 442                 return -1;
 443         }
 444
 445         if (present[TCA_NETEM_ECN]) {
 446                 if (opt.loss <= 0 && loss_type == NETEM_LOSS_UNSPEC) {
 447                         fprintf(stderr, "ecn requested without loss model\n");
 448                         explain();
 449                         return -1;
 450                 }
 451         }
 452
 453         if (dist_data && (opt.latency == 0 || opt.jitter == 0)) {
 454                 fprintf(stderr, "distribution specified but no latency and jitter values\n");
 455                 explain();
 456                 return -1;
 457         }
 458
 459         if (addattr_l(n, 1024, TCA_OPTIONS, &opt, sizeof(opt)) < 0)
 460                 return -1;
 461
 462         if (present[TCA_NETEM_CORR] &&
 463             addattr_l(n, 1024, TCA_NETEM_CORR, &cor, sizeof(cor)) < 0)
 464                         return -1;
 465
 466         if (present[TCA_NETEM_REORDER] &&
 467             addattr_l(n, 1024, TCA_NETEM_REORDER, &reorder, sizeof(reorder)) < 0)
 468                 return -1;
 469
 470         if (present[TCA_NETEM_ECN] &&
 471             addattr_l(n, 1024, TCA_NETEM_ECN, &present[TCA_NETEM_ECN],
 472                       sizeof(present[TCA_NETEM_ECN])) < 0)
 473                         return -1;
 474
 475         if (present[TCA_NETEM_CORRUPT] &&
 476             addattr_l(n, 1024, TCA_NETEM_CORRUPT, &corrupt, sizeof(corrupt)) < 0)
 477                 return -1;
 478
 479         if (loss_type != NETEM_LOSS_UNSPEC) {
 480                 struct rtattr *start;
 481
 482                 start = addattr_nest(n, 1024, TCA_NETEM_LOSS | NLA_F_NESTED);
 483                 if (loss_type == NETEM_LOSS_GI) {
 484                         if (addattr_l(n, 1024, NETEM_LOSS_GI,
 485                                       &gimodel, sizeof(gimodel)) < 0)
 486                             return -1;
 487                 } else if (loss_type == NETEM_LOSS_GE) {
 488                         if (addattr_l(n, 1024, NETEM_LOSS_GE,
 489                                       &gemodel, sizeof(gemodel)) < 0)
 490                             return -1;
 491                 } else {
 492                         fprintf(stderr, "loss in the weeds!\n");
 493                         return -1;
 494                 }
 495
 496                 addattr_nest_end(n, start);
 497         }
 498
 499         if (present[TCA_NETEM_RATE] &&
 500             addattr_l(n, 1024, TCA_NETEM_RATE, &rate, sizeof(rate)) < 0)
 501                 return -1;
 502
 503         if (dist_data) {
 504                 if (addattr_l(n, MAX_DIST * sizeof(dist_data[0]),
 505                               TCA_NETEM_DELAY_DIST,
 506                               dist_data, dist_size * sizeof(dist_data[0])) < 0)
 507                         return -1;
 508                 free(dist_data);
 509         }
 510         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
 511         return 0;
 512 }
 513
 514 static int netem_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 515 {
 516         const struct tc_netem_corr *cor = NULL;
 517         const struct tc_netem_reorder *reorder = NULL;
 518         const struct tc_netem_corrupt *corrupt = NULL;
 519         const struct tc_netem_gimodel *gimodel = NULL;
 520         const struct tc_netem_gemodel *gemodel = NULL;
 521         int *ecn = NULL;
 522         struct tc_netem_qopt qopt;
 523         const struct tc_netem_rate *rate = NULL;
 524         int len = RTA_PAYLOAD(opt) - sizeof(qopt);
 525         SPRINT_BUF(b1);
 526
 527         if (opt == NULL)
 528                 return 0;
 529
 530         if (len < 0) {
 531                 fprintf(stderr, "options size error\n");
 532                 return -1;
 533         }
 534         memcpy(&qopt, RTA_DATA(opt), sizeof(qopt));
 535
 536         if (len > 0) {
 537                 struct rtattr *tb[TCA_NETEM_MAX+1];
 538                 parse_rtattr(tb, TCA_NETEM_MAX, RTA_DATA(opt) + sizeof(qopt),
 539                              len);
 540
 541                 if (tb[TCA_NETEM_CORR]) {
 542                         if (RTA_PAYLOAD(tb[TCA_NETEM_CORR]) < sizeof(*cor))
 543                                 return -1;
 544                         cor = RTA_DATA(tb[TCA_NETEM_CORR]);
 545                 }
 546                 if (tb[TCA_NETEM_REORDER]) {
 547                         if (RTA_PAYLOAD(tb[TCA_NETEM_REORDER]) < sizeof(*reorder))
 548                                 return -1;
 549                         reorder = RTA_DATA(tb[TCA_NETEM_REORDER]);
 550                 }
 551                 if (tb[TCA_NETEM_CORRUPT]) {
 552                         if (RTA_PAYLOAD(tb[TCA_NETEM_CORRUPT]) < sizeof(*corrupt))
 553                                 return -1;
 554                         corrupt = RTA_DATA(tb[TCA_NETEM_CORRUPT]);
 555                 }
 556                 if (tb[TCA_NETEM_LOSS]) {
 557                         struct rtattr *lb[NETEM_LOSS_MAX + 1];
 558
 559                         parse_rtattr_nested(lb, NETEM_LOSS_MAX, tb[TCA_NETEM_LOSS]);
 560                         if (lb[NETEM_LOSS_GI])
 561                                 gemodel = RTA_DATA(lb[NETEM_LOSS_GI]);
 562                         if (lb[NETEM_LOSS_GE])
 563                                 gemodel = RTA_DATA(lb[NETEM_LOSS_GE]);
 564                 }
 565                 if (tb[TCA_NETEM_RATE]) {
 566                         if (RTA_PAYLOAD(tb[TCA_NETEM_RATE]) < sizeof(*rate))
 567                                 return -1;
 568                         rate = RTA_DATA(tb[TCA_NETEM_RATE]);
 569                 }
 570                 if (tb[TCA_NETEM_ECN]) {
 571                         if (RTA_PAYLOAD(tb[TCA_NETEM_ECN]) < sizeof(*ecn))
 572                                 return -1;
 573                         ecn = RTA_DATA(tb[TCA_NETEM_ECN]);
 574                 }
 575         }
 576
 577         fprintf(f, "limit %d", qopt.limit);
 578
 579         if (qopt.latency) {
 580                 fprintf(f, " delay %s", sprint_ticks(qopt.latency, b1));
 581
 582                 if (qopt.jitter) {
 583                         fprintf(f, "  %s", sprint_ticks(qopt.jitter, b1));
 584                         if (cor && cor->delay_corr)
 585                                 fprintf(f, " %s", sprint_percent(cor->delay_corr, b1));
 586                 }
 587         }
 588
 589         if (qopt.loss) {
 590                 fprintf(f, " loss %s", sprint_percent(qopt.loss, b1));
 591                 if (cor && cor->loss_corr)
 592                         fprintf(f, " %s", sprint_percent(cor->loss_corr, b1));
 593         }
 594
 595         if (gimodel) {
 596                 fprintf(f, " loss state p13 %s", sprint_percent(gimodel->p13, b1));
 597                 fprintf(f, " p31 %s", sprint_percent(gimodel->p31, b1));
 598                 fprintf(f, " p32 %s", sprint_percent(gimodel->p32, b1));
 599                 fprintf(f, " p23 %s", sprint_percent(gimodel->p23, b1));
 600                 fprintf(f, " p14 %s", sprint_percent(gimodel->p14, b1));
 601         }
 602
 603         if (gemodel) {
 604                 fprintf(f, "loss gemodel p %s",
 605                         sprint_percent(gemodel->p, b1));
 606                 fprintf(f, " r %s", sprint_percent(gemodel->r, b1));
 607                 fprintf(f, " 1-h %s", sprint_percent(gemodel->h, b1));
 608                 fprintf(f, " 1-k %s", sprint_percent(gemodel->k1, b1));
 609         }
 610
 611         if (qopt.duplicate) {
 612                 fprintf(f, " duplicate %s",
 613                         sprint_percent(qopt.duplicate, b1));
 614                 if (cor && cor->dup_corr)
 615                         fprintf(f, " %s", sprint_percent(cor->dup_corr, b1));
 616         }
 617
 618         if (reorder && reorder->probability) {
 619                 fprintf(f, " reorder %s",
 620                         sprint_percent(reorder->probability, b1));
 621                 if (reorder->correlation)
 622                         fprintf(f, " %s",
 623                                 sprint_percent(reorder->correlation, b1));
 624         }
 625
 626         if (corrupt && corrupt->probability) {
 627                 fprintf(f, " corrupt %s",
 628                         sprint_percent(corrupt->probability, b1));
 629                 if (corrupt->correlation)
 630                         fprintf(f, " %s",
 631                                 sprint_percent(corrupt->correlation, b1));
 632         }
 633
 634         if (rate && rate->rate) {
 635                 fprintf(f, " rate %s", sprint_rate(rate->rate, b1));
 636                 if (rate->packet_overhead)
 637                         fprintf(f, " packetoverhead %d", rate->packet_overhead);
 638                 if (rate->cell_size)
 639                         fprintf(f, " cellsize %u", rate->cell_size);
 640                 if (rate->cell_overhead)
 641                         fprintf(f, " celloverhead %d", rate->cell_overhead);
 642         }
 643
 644         if (ecn)
 645                 fprintf(f, " ecn ");
 646
 647         if (qopt.gap)
 648                 fprintf(f, " gap %lu", (unsigned long)qopt.gap);
 649
 650
 651         return 0;
 652 }
 653
 654 struct qdisc_util netem_qdisc_util = {
 655         .id             = "netem",
 656         .parse_qopt     = netem_parse_opt,
 657         .print_qopt     = netem_print_opt,
 658 };
 659