/*
* q_netem.c NETEM.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Authors: Stephen Hemminger <shemminger@osdl.org>
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <syslog.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <errno.h>
#include "utils.h"
#include "tc_util.h"
#include "tc_common.h"
static void explain(void)
{
fprintf(stderr,
"Usage: ... netem [ limit PACKETS ] \n" \
" [ delay TIME [ JITTER [CORRELATION]]]\n" \
" [ distribution {uniform|normal|pareto|paretonormal} ]\n" \
" [ drop PERCENT [CORRELATION]] \n" \
" [ corrupt PERCENT [CORRELATION]] \n" \
" [ duplicate PERCENT [CORRELATION]]\n" \
" [ reorder PRECENT [CORRELATION] [ gap DISTANCE ]]\n");
}
static void explain1(const char *arg)
{
fprintf(stderr, "Illegal \"%s\"\n", arg);
}
/* Upper bound on size of distribution
* really (TCA_BUF_MAX - other headers) / sizeof (__s16)
*/
#define MAX_DIST (16*1024)
/*
* Simplistic file parser for distrbution data.
* Format is:
* # comment line(s)
* data0 data1 ...
*/
static int get_distribution(const char *type, __s16 *data, int maxdata)
{
FILE *f;
int n;
long x;
size_t len;
char *line = NULL;
char name[128];
snprintf(name, sizeof(name), "%s/%s.dist", get_tc_lib(), type);
if ((f = fopen(name, "r")) == NULL) {
fprintf(stderr, "No distribution data for %s (%s: %s)\n",
type, name, strerror(errno));
return -1;
}
n = 0;
while (getline(&line, &len, f) != -1) {
char *p, *endp;
if (*line == '\n' || *line == '#')
continue;
for (p = line; ; p = endp) {
x = strtol(p, &endp, 0);
if (endp == p)
break;
if (n >= maxdata) {
fprintf(stderr, "%s: too much data\n",
name);
n = -1;
goto error;
}
data[n++] = x;
}
}
error:
free(line);
fclose(f);
return n;
}
static int isnumber(const char *arg)
{
char *p;
return strtod(arg, &p) != 0 || p != arg;
}
#define NEXT_IS_NUMBER() (NEXT_ARG_OK() && isnumber(argv[1]))
/* Adjust for the fact that psched_ticks aren't always usecs
(based on kernel PSCHED_CLOCK configuration */
static int get_ticks(__u32 *ticks, const char *str)
{
unsigned t;
if(get_time(&t, str))
return -1;
if (tc_core_time2big(t)) {
fprintf(stderr, "Illegal %u time (too large)\n", t);
return -1;
}
*ticks = tc_core_time2tick(t);
return 0;
}
static int netem_parse_opt(struct qdisc_util *qu, int argc, char **argv,
struct nlmsghdr *n)
{
size_t dist_size = 0;
struct rtattr *tail;
struct tc_netem_qopt opt;
struct tc_netem_corr cor;
struct tc_netem_reorder reorder;
struct tc_netem_corrupt corrupt;
__s16 *dist_data = NULL;
int present[__TCA_NETEM_MAX];
memset(&opt, 0, sizeof(opt));
opt.limit = 1000;
memset(&cor, 0, sizeof(cor));
memset(&reorder, 0, sizeof(reorder));
memset(&corrupt, 0, sizeof(corrupt));
memset(present, 0, sizeof(present));
while (argc > 0) {
if (matches(*argv, "limit") == 0) {
NEXT_ARG();
if (get_size(&opt.limit, *argv)) {
explain1("limit");
return -1;
}
} else if (matches(*argv, "latency") == 0 ||
matches(*argv, "delay") == 0) {
NEXT_ARG();
if (get_ticks(&opt.latency, *argv)) {
explain1("latency");
return -1;
}
if (NEXT_IS_NUMBER()) {
NEXT_ARG();
if (get_ticks(&opt.jitter, *argv)) {
explain1("latency");
return -1;
}
if (NEXT_IS_NUMBER()) {
NEXT_ARG();
++present[TCA_NETEM_CORR];
if (get_percent(&cor.delay_corr, *argv)) {
explain1("latency");
return -1;
}
}
}
} else if (matches(*argv, "loss") == 0 ||
matches(*argv, "drop") == 0) {
NEXT_ARG();
if (get_percent(&opt.loss, *argv)) {
explain1("loss");
return -1;
}
if (NEXT_IS_NUMBER()) {
NEXT_ARG();
++present[TCA_NETEM_CORR];
if (get_percent(&cor.loss_corr, *argv)) {
explain1("loss");
return -1;
}
}
} else if (matches(*argv, "reorder") == 0) {
NEXT_ARG();
present[TCA_NETEM_REORDER] = 1;
if (get_percent(&reorder.probability, *argv)) {
explain1("reorder");
return -1;
}
if (NEXT_IS_NUMBER()) {
NEXT_ARG();
++present[TCA_NETEM_CORR];
if (get_percent(&reorder.correlation, *argv)) {
explain1("reorder");
return -1;
}
}
} else if (matches(*argv, "corrupt") == 0) {
NEXT_ARG();
present[TCA_NETEM_CORRUPT] = 1;
if (get_percent(&corrupt.probability, *argv)) {
explain1("corrupt");
return -1;
}
if (NEXT_IS_NUMBER()) {
NEXT_ARG();
++present[TCA_NETEM_CORR];
if (get_percent(&corrupt.correlation, *argv)) {
explain1("corrupt");
return -1;
}
}
} else if (matches(*argv, "gap") == 0) {
NEXT_ARG();
if (get_u32(&opt.gap, *argv, 0)) {
explain1("gap");
return -1;
}
} else if (matches(*argv, "duplicate") == 0) {
NEXT_ARG();
if (get_percent(&opt.duplicate, *argv)) {
explain1("duplicate");
return -1;
}
if (NEXT_IS_NUMBER()) {
NEXT_ARG();
if (get_percent(&cor.dup_corr, *argv)) {
explain1("duplicate");
return -1;
}
}
} else if (matches(*argv, "distribution") == 0) {
NEXT_ARG();
dist_data = calloc(sizeof(dist_data[0]), MAX_DIST);
dist_size = get_distribution(*argv, dist_data, MAX_DIST);
if (dist_size <= 0) {
free(dist_data);
return -1;
}
} else if (strcmp(*argv, "help") == 0) {
explain();
return -1;
} else {
fprintf(stderr, "What is \"%s\"?\n", *argv);
explain();
return -1;
}
argc--; argv++;
}
tail = NLMSG_TAIL(n);
if (reorder.probability) {
if (opt.latency == 0) {
fprintf(stderr, "reordering not possible without specifying some delay\n");
}
if (opt.gap == 0)
opt.gap = 1;
} else if (opt.gap > 0) {
fprintf(stderr, "gap specified without reorder probability\n");
explain();
return -1;
}
if (dist_data && (opt.latency == 0 || opt.jitter == 0)) {
fprintf(stderr, "distribution specified but no latency and jitter values\n");
explain();
return -1;
}
if (addattr_l(n, 1024, TCA_OPTIONS, &opt, sizeof(opt)) < 0)
return -1;
if (present[TCA_NETEM_CORR] &&
addattr_l(n, 1024, TCA_NETEM_CORR, &cor, sizeof(cor)) < 0)
return -1;
if (present[TCA_NETEM_REORDER] &&
addattr_l(n, 1024, TCA_NETEM_REORDER, &reorder, sizeof(reorder)) < 0)
return -1;
if (present[TCA_NETEM_CORRUPT] &&
addattr_l(n, 1024, TCA_NETEM_CORRUPT, &corrupt, sizeof(corrupt)) < 0)
return -1;
if (dist_data) {
if (addattr_l(n, MAX_DIST * sizeof(dist_data[0]),
TCA_NETEM_DELAY_DIST,
dist_data, dist_size * sizeof(dist_data[0])) < 0)
return -1;
free(dist_data);
}
tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
return 0;
}
static int netem_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
{
const struct tc_netem_corr *cor = NULL;
const struct tc_netem_reorder *reorder = NULL;
const struct tc_netem_corrupt *corrupt = NULL;
struct tc_netem_qopt qopt;
int len = RTA_PAYLOAD(opt) - sizeof(qopt);
SPRINT_BUF(b1);
if (opt == NULL)
return 0;
if (len < 0) {
fprintf(stderr, "options size error\n");
return -1;
}
memcpy(&qopt, RTA_DATA(opt), sizeof(qopt));
if (len > 0) {
struct rtattr *tb[TCA_NETEM_MAX+1];
parse_rtattr(tb, TCA_NETEM_MAX, RTA_DATA(opt) + sizeof(qopt),
len);
if (tb[TCA_NETEM_CORR]) {
if (RTA_PAYLOAD(tb[TCA_NETEM_CORR]) < sizeof(*cor))
return -1;
cor = RTA_DATA(tb[TCA_NETEM_CORR]);
}
if (tb[TCA_NETEM_REORDER]) {
if (RTA_PAYLOAD(tb[TCA_NETEM_REORDER]) < sizeof(*reorder))
return -1;
reorder = RTA_DATA(tb[TCA_NETEM_REORDER]);
}
if (tb[TCA_NETEM_CORRUPT]) {
if (RTA_PAYLOAD(tb[TCA_NETEM_CORRUPT]) < sizeof(*corrupt))
return -1;
corrupt = RTA_DATA(tb[TCA_NETEM_CORRUPT]);
}
}
fprintf(f, "limit %d", qopt.limit);
if (qopt.latency) {
fprintf(f, " delay %s", sprint_ticks(qopt.latency, b1));
if (qopt.jitter) {
fprintf(f, " %s", sprint_ticks(qopt.jitter, b1));
if (cor && cor->delay_corr)
fprintf(f, " %s", sprint_percent(cor->delay_corr, b1));
}
}
if (qopt.loss) {
fprintf(f, " loss %s", sprint_percent(qopt.loss, b1));
if (cor && cor->loss_corr)
fprintf(f, " %s", sprint_percent(cor->loss_corr, b1));
}
if (qopt.duplicate) {
fprintf(f, " duplicate %s",
sprint_percent(qopt.duplicate, b1));
if (cor && cor->dup_corr)
fprintf(f, " %s", sprint_percent(cor->dup_corr, b1));
}
if (reorder && reorder->probability) {
fprintf(f, " reorder %s",
sprint_percent(reorder->probability, b1));
if (reorder->correlation)
fprintf(f, " %s",
sprint_percent(reorder->correlation, b1));
}
if (corrupt && corrupt->probability) {
fprintf(f, " corrupt %s",
sprint_percent(corrupt->probability, b1));
if (corrupt->correlation)
fprintf(f, " %s",
sprint_percent(corrupt->correlation, b1));
}
if (qopt.gap)
fprintf(f, " gap %lu", (unsigned long)qopt.gap);
return 0;
}
struct qdisc_util netem_qdisc_util = {
.id = "netem",
.parse_qopt = netem_parse_opt,
.print_qopt = netem_print_opt,
};