blob: 279205004e0542f88264cb0ed7fdaa2dd66add22 [file] [log] [blame]
/* Shared library add-on to iptables to add connection rate tracking
* support.
*
* Copyright (c) 2004 Nuutti Kotivuori <naked@iki.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
**/
#include <stdio.h>
#include <netdb.h>
#include <string.h>
#include <stdlib.h>
#include <getopt.h>
#include <iptables.h>
#include <linux/netfilter/nf_conntrack_common.h>
#include <linux/netfilter_ipv4/ipt_connrate.h>
/* Function which prints out usage message. */
static void
help(void)
{
printf(
"connrate v%s options:\n"
" --connrate [!] [from]:[to]\n"
" Match connection transfer rate in bytes\n"
" per second. `inf' can be used for maximum\n"
" expressible value.\n"
"\n", IPTABLES_VERSION);
}
static struct option opts[] = {
{ "connrate", 1, 0, '1' },
{0}
};
static u_int32_t
parse_value(const char *arg, u_int32_t def)
{
char *end;
size_t len;
u_int32_t value;
len = strlen(arg);
if(len == 0)
return def;
if(strcmp(arg, "inf") == 0)
return 0xFFFFFFFF;
value = strtoul(arg, &end, 0);
if(*end != '\0')
exit_error(PARAMETER_PROBLEM,
"Bad value in range `%s'", arg);
return value;
}
static void
parse_range(const char *arg, struct ipt_connrate_info *si)
{
char *buffer;
char *colon;
buffer = strdup(arg);
if ((colon = strchr(buffer, ':')) == NULL)
exit_error(PARAMETER_PROBLEM, "Bad range `%s'", arg);
*colon = '\0';
si->from = parse_value(buffer, 0);
si->to = parse_value(colon+1, 0xFFFFFFFF);
if (si->from > si->to)
exit_error(PARAMETER_PROBLEM, "%u should be less than %u", si->from,si->to);
free(buffer);
}
#define CONNRATE_OPT 0x01
/* Function which parses command options; returns true if it
ate an option */
static int
parse(int c, char **argv, int invert, unsigned int *flags,
const void *entry,
unsigned int *nfcache,
struct xt_entry_match **match)
{
struct ipt_connrate_info *sinfo = (struct ipt_connrate_info *)(*match)->data;
u_int32_t tmp;
switch (c) {
case '1':
if (*flags & CONNRATE_OPT)
exit_error(PARAMETER_PROBLEM,
"Only one `--connrate' allowed");
check_inverse(optarg, &invert, &optind, 0);
parse_range(argv[optind-1], sinfo);
if (invert) {
tmp = sinfo->from;
sinfo->from = sinfo->to;
sinfo->to = tmp;
}
*flags |= CONNRATE_OPT;
break;
default:
return 0;
}
return 1;
}
static void final_check(unsigned int flags)
{
if (!(flags & CONNRATE_OPT))
exit_error(PARAMETER_PROBLEM,
"connrate match: You must specify `--connrate'");
}
static void
print_value(u_int32_t value)
{
if(value == 0xFFFFFFFF)
printf("inf");
else
printf("%u", value);
}
static void
print_range(struct ipt_connrate_info *sinfo)
{
if (sinfo->from > sinfo->to) {
printf("! ");
print_value(sinfo->to);
printf(":");
print_value(sinfo->from);
} else {
print_value(sinfo->from);
printf(":");
print_value(sinfo->to);
}
}
/* Prints out the matchinfo. */
static void
print(const void *ip,
const struct xt_entry_match *match,
int numeric)
{
struct ipt_connrate_info *sinfo = (struct ipt_connrate_info *)match->data;
printf("connrate ");
print_range(sinfo);
printf(" ");
}
/* Saves the matchinfo in parsable form to stdout. */
static void save(const void *ip, const struct xt_entry_match *match)
{
struct ipt_connrate_info *sinfo = (struct ipt_connrate_info *)match->data;
printf("--connrate ");
print_range(sinfo);
printf(" ");
}
static struct iptables_match state = {
.next = NULL,
.name = "connrate",
.version = IPTABLES_VERSION,
.size = IPT_ALIGN(sizeof(struct ipt_connrate_info)),
.userspacesize = IPT_ALIGN(sizeof(struct ipt_connrate_info)),
.help = &help,
.parse = &parse,
.final_check = &final_check,
.print = &print,
.save = &save,
.extra_opts = opts
};
void _init(void)
{
register_match(&state);
}