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 (at) osdl.org> 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 <errno.h> 23 24 #include "utils.h" 25 #include "tc_util.h" 26 #include "tc_common.h" 27 28 static void explain(void) 29 { 30 fprintf(stderr, 31 "Usage: ... netem [ limit PACKETS ] \n" \ 32 " [ delay TIME [ JITTER [CORRELATION]]]\n" \ 33 " [ distribution {uniform|normal|pareto|paretonormal} ]\n" \ 34 " [ drop PERCENT [CORRELATION]] \n" \ 35 " [ corrupt PERCENT [CORRELATION]] \n" \ 36 " [ duplicate PERCENT [CORRELATION]]\n" \ 37 " [ reorder PRECENT [CORRELATION] [ gap DISTANCE ]]\n"); 38 } 39 40 static void explain1(const char *arg) 41 { 42 fprintf(stderr, "Illegal \"%s\"\n", arg); 43 } 44 45 /* Upper bound on size of distribution 46 * really (TCA_BUF_MAX - other headers) / sizeof (__s16) 47 */ 48 #define MAX_DIST (16*1024) 49 50 /* 51 * Simplistic file parser for distrbution data. 52 * Format is: 53 * # comment line(s) 54 * data0 data1 ... 55 */ 56 static int get_distribution(const char *type, __s16 *data, int maxdata) 57 { 58 FILE *f; 59 int n; 60 long x; 61 size_t len; 62 char *line = NULL; 63 char name[128]; 64 65 snprintf(name, sizeof(name), "%s/%s.dist", get_tc_lib(), type); 66 if ((f = fopen(name, "r")) == NULL) { 67 fprintf(stderr, "No distribution data for %s (%s: %s)\n", 68 type, name, strerror(errno)); 69 return -1; 70 } 71 72 n = 0; 73 while (getline(&line, &len, f) != -1) { 74 char *p, *endp; 75 if (*line == '\n' || *line == '#') 76 continue; 77 78 for (p = line; ; p = endp) { 79 x = strtol(p, &endp, 0); 80 if (endp == p) 81 break; 82 83 if (n >= maxdata) { 84 fprintf(stderr, "%s: too much data\n", 85 name); 86 n = -1; 87 goto error; 88 } 89 data[n++] = x; 90 } 91 } 92 error: 93 free(line); 94 fclose(f); 95 return n; 96 } 97 98 static int isnumber(const char *arg) 99 { 100 char *p; 101 102 return strtod(arg, &p) != 0 || p != arg; 103 } 104 105 #define NEXT_IS_NUMBER() (NEXT_ARG_OK() && isnumber(argv[1])) 106 107 /* Adjust for the fact that psched_ticks aren't always usecs 108 (based on kernel PSCHED_CLOCK configuration */ 109 static int get_ticks(__u32 *ticks, const char *str) 110 { 111 unsigned t; 112 113 if(get_time(&t, str)) 114 return -1; 115 116 if (tc_core_time2big(t)) { 117 fprintf(stderr, "Illegal %u time (too large)\n", t); 118 return -1; 119 } 120 121 *ticks = tc_core_time2tick(t); 122 return 0; 123 } 124 125 static int netem_parse_opt(struct qdisc_util *qu, int argc, char **argv, 126 struct nlmsghdr *n) 127 { 128 size_t dist_size = 0; 129 struct rtattr *tail; 130 struct tc_netem_qopt opt; 131 struct tc_netem_corr cor; 132 struct tc_netem_reorder reorder; 133 struct tc_netem_corrupt corrupt; 134 __s16 *dist_data = NULL; 135 int present[__TCA_NETEM_MAX]; 136 137 memset(&opt, 0, sizeof(opt)); 138 opt.limit = 1000; 139 memset(&cor, 0, sizeof(cor)); 140 memset(&reorder, 0, sizeof(reorder)); 141 memset(&corrupt, 0, sizeof(corrupt)); 142 memset(present, 0, sizeof(present)); 143 144 while (argc > 0) { 145 if (matches(*argv, "limit") == 0) { 146 NEXT_ARG(); 147 if (get_size(&opt.limit, *argv)) { 148 explain1("limit"); 149 return -1; 150 } 151 } else if (matches(*argv, "latency") == 0 || 152 matches(*argv, "delay") == 0) { 153 NEXT_ARG(); 154 if (get_ticks(&opt.latency, *argv)) { 155 explain1("latency"); 156 return -1; 157 } 158 159 if (NEXT_IS_NUMBER()) { 160 NEXT_ARG(); 161 if (get_ticks(&opt.jitter, *argv)) { 162 explain1("latency"); 163 return -1; 164 } 165 166 if (NEXT_IS_NUMBER()) { 167 NEXT_ARG(); 168 ++present[TCA_NETEM_CORR]; 169 if (get_percent(&cor.delay_corr, *argv)) { 170 explain1("latency"); 171 return -1; 172 } 173 } 174 } 175 } else if (matches(*argv, "loss") == 0 || 176 matches(*argv, "drop") == 0) { 177 NEXT_ARG(); 178 if (get_percent(&opt.loss, *argv)) { 179 explain1("loss"); 180 return -1; 181 } 182 if (NEXT_IS_NUMBER()) { 183 NEXT_ARG(); 184 ++present[TCA_NETEM_CORR]; 185 if (get_percent(&cor.loss_corr, *argv)) { 186 explain1("loss"); 187 return -1; 188 } 189 } 190 } else if (matches(*argv, "reorder") == 0) { 191 NEXT_ARG(); 192 present[TCA_NETEM_REORDER] = 1; 193 if (get_percent(&reorder.probability, *argv)) { 194 explain1("reorder"); 195 return -1; 196 } 197 if (NEXT_IS_NUMBER()) { 198 NEXT_ARG(); 199 ++present[TCA_NETEM_CORR]; 200 if (get_percent(&reorder.correlation, *argv)) { 201 explain1("reorder"); 202 return -1; 203 } 204 } 205 } else if (matches(*argv, "corrupt") == 0) { 206 NEXT_ARG(); 207 present[TCA_NETEM_CORRUPT] = 1; 208 if (get_percent(&corrupt.probability, *argv)) { 209 explain1("corrupt"); 210 return -1; 211 } 212 if (NEXT_IS_NUMBER()) { 213 NEXT_ARG(); 214 ++present[TCA_NETEM_CORR]; 215 if (get_percent(&corrupt.correlation, *argv)) { 216 explain1("corrupt"); 217 return -1; 218 } 219 } 220 } else if (matches(*argv, "gap") == 0) { 221 NEXT_ARG(); 222 if (get_u32(&opt.gap, *argv, 0)) { 223 explain1("gap"); 224 return -1; 225 } 226 } else if (matches(*argv, "duplicate") == 0) { 227 NEXT_ARG(); 228 if (get_percent(&opt.duplicate, *argv)) { 229 explain1("duplicate"); 230 return -1; 231 } 232 if (NEXT_IS_NUMBER()) { 233 NEXT_ARG(); 234 if (get_percent(&cor.dup_corr, *argv)) { 235 explain1("duplicate"); 236 return -1; 237 } 238 } 239 } else if (matches(*argv, "distribution") == 0) { 240 NEXT_ARG(); 241 dist_data = calloc(sizeof(dist_data[0]), MAX_DIST); 242 dist_size = get_distribution(*argv, dist_data, MAX_DIST); 243 if (dist_size <= 0) { 244 free(dist_data); 245 return -1; 246 } 247 } else if (strcmp(*argv, "help") == 0) { 248 explain(); 249 return -1; 250 } else { 251 fprintf(stderr, "What is \"%s\"?\n", *argv); 252 explain(); 253 return -1; 254 } 255 argc--; argv++; 256 } 257 258 tail = NLMSG_TAIL(n); 259 260 if (reorder.probability) { 261 if (opt.latency == 0) { 262 fprintf(stderr, "reordering not possible without specifying some delay\n"); 263 } 264 if (opt.gap == 0) 265 opt.gap = 1; 266 } else if (opt.gap > 0) { 267 fprintf(stderr, "gap specified without reorder probability\n"); 268 explain(); 269 return -1; 270 } 271 272 if (dist_data && (opt.latency == 0 || opt.jitter == 0)) { 273 fprintf(stderr, "distribution specified but no latency and jitter values\n"); 274 explain(); 275 return -1; 276 } 277 278 if (addattr_l(n, 1024, TCA_OPTIONS, &opt, sizeof(opt)) < 0) 279 return -1; 280 281 if (present[TCA_NETEM_CORR] && 282 addattr_l(n, 1024, TCA_NETEM_CORR, &cor, sizeof(cor)) < 0) 283 return -1; 284 285 if (present[TCA_NETEM_REORDER] && 286 addattr_l(n, 1024, TCA_NETEM_REORDER, &reorder, sizeof(reorder)) < 0) 287 return -1; 288 289 if (present[TCA_NETEM_CORRUPT] && 290 addattr_l(n, 1024, TCA_NETEM_CORRUPT, &corrupt, sizeof(corrupt)) < 0) 291 return -1; 292 293 if (dist_data) { 294 if (addattr_l(n, MAX_DIST * sizeof(dist_data[0]), 295 TCA_NETEM_DELAY_DIST, 296 dist_data, dist_size * sizeof(dist_data[0])) < 0) 297 return -1; 298 free(dist_data); 299 } 300 tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail; 301 return 0; 302 } 303 304 static int netem_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt) 305 { 306 const struct tc_netem_corr *cor = NULL; 307 const struct tc_netem_reorder *reorder = NULL; 308 const struct tc_netem_corrupt *corrupt = NULL; 309 struct tc_netem_qopt qopt; 310 int len = RTA_PAYLOAD(opt) - sizeof(qopt); 311 SPRINT_BUF(b1); 312 313 if (opt == NULL) 314 return 0; 315 316 if (len < 0) { 317 fprintf(stderr, "options size error\n"); 318 return -1; 319 } 320 memcpy(&qopt, RTA_DATA(opt), sizeof(qopt)); 321 322 if (len > 0) { 323 struct rtattr *tb[TCA_NETEM_MAX+1]; 324 parse_rtattr(tb, TCA_NETEM_MAX, RTA_DATA(opt) + sizeof(qopt), 325 len); 326 327 if (tb[TCA_NETEM_CORR]) { 328 if (RTA_PAYLOAD(tb[TCA_NETEM_CORR]) < sizeof(*cor)) 329 return -1; 330 cor = RTA_DATA(tb[TCA_NETEM_CORR]); 331 } 332 if (tb[TCA_NETEM_REORDER]) { 333 if (RTA_PAYLOAD(tb[TCA_NETEM_REORDER]) < sizeof(*reorder)) 334 return -1; 335 reorder = RTA_DATA(tb[TCA_NETEM_REORDER]); 336 } 337 if (tb[TCA_NETEM_CORRUPT]) { 338 if (RTA_PAYLOAD(tb[TCA_NETEM_CORRUPT]) < sizeof(*corrupt)) 339 return -1; 340 corrupt = RTA_DATA(tb[TCA_NETEM_CORRUPT]); 341 } 342 } 343 344 fprintf(f, "limit %d", qopt.limit); 345 346 if (qopt.latency) { 347 fprintf(f, " delay %s", sprint_ticks(qopt.latency, b1)); 348 349 if (qopt.jitter) { 350 fprintf(f, " %s", sprint_ticks(qopt.jitter, b1)); 351 if (cor && cor->delay_corr) 352 fprintf(f, " %s", sprint_percent(cor->delay_corr, b1)); 353 } 354 } 355 356 if (qopt.loss) { 357 fprintf(f, " loss %s", sprint_percent(qopt.loss, b1)); 358 if (cor && cor->loss_corr) 359 fprintf(f, " %s", sprint_percent(cor->loss_corr, b1)); 360 } 361 362 if (qopt.duplicate) { 363 fprintf(f, " duplicate %s", 364 sprint_percent(qopt.duplicate, b1)); 365 if (cor && cor->dup_corr) 366 fprintf(f, " %s", sprint_percent(cor->dup_corr, b1)); 367 } 368 369 if (reorder && reorder->probability) { 370 fprintf(f, " reorder %s", 371 sprint_percent(reorder->probability, b1)); 372 if (reorder->correlation) 373 fprintf(f, " %s", 374 sprint_percent(reorder->correlation, b1)); 375 } 376 377 if (corrupt && corrupt->probability) { 378 fprintf(f, " corrupt %s", 379 sprint_percent(corrupt->probability, b1)); 380 if (corrupt->correlation) 381 fprintf(f, " %s", 382 sprint_percent(corrupt->correlation, b1)); 383 } 384 385 if (qopt.gap) 386 fprintf(f, " gap %lu", (unsigned long)qopt.gap); 387 388 return 0; 389 } 390 391 struct qdisc_util netem_qdisc_util = { 392 .id = "netem", 393 .parse_qopt = netem_parse_opt, 394 .print_qopt = netem_print_opt, 395 }; 396 397
