#define BUILD_MATCH
#define MODULE_DATATYPE struct ipt_rateinfo
#define MODULE_NAME "limit"
#define __USE_GNU
#include "../module_iface.h"
#include <string.h>
#include <stdio.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv4/ipt_limit.h>
#define DEFAULT_BURST 5
#define DEFAULT_LIMIT IPT_LIMIT_SCALE * 3600 / 3
static struct RateList
{
char *name, *alias;
u_int32_t mult;
} rate_list[] = {
{ "day", "day", IPT_LIMIT_SCALE*24*60*60 },
{ "hour", "hr", IPT_LIMIT_SCALE*60*60 },
{ "min", "minute", IPT_LIMIT_SCALE*60 },
{ "sec", "second", IPT_LIMIT_SCALE }
};
static int parse_rate_sv(SV *sv, struct ipt_rateinfo *rate) {
char *ratestr, *sep, *extent;
int factor = 1, value;
if(SvIOK(sv)) {
value = IPT_LIMIT_SCALE / SvIV(sv);
}
else if(SvPOK(sv)) {
char *temp;
STRLEN len;
temp = SvPV(sv, len);
ratestr = malloc(len + 1);
strncpy(ratestr, temp, len);
ratestr[len] = '\0';
sep = strchr(ratestr, '/');
value = strtoul(ratestr, &extent, 10);
if(extent < (sep ? sep : (ratestr + strlen(ratestr)))) {
free(ratestr);
return(FALSE);
}
if(sep) {
sep++;
if(!strcasecmp(sep, "second") || !strcasecmp(sep, "sec"))
factor = 1;
else if(!strcasecmp(sep, "minute") || !strcasecmp(sep, "min"))
factor = 60;
else if(!strcasecmp(sep, "hour") || !strcasecmp(sep, "hr"))
factor = 60 * 60;
else if(!strcasecmp(sep, "day"))
factor = 60 * 60 * 24;
else {
free(ratestr);
return(FALSE);
}
}
free(ratestr);
}
else
return(FALSE);
if((value <= 0) || (value / factor > IPT_LIMIT_SCALE))
return(FALSE);
rate->avg = IPT_LIMIT_SCALE * factor / value;
return(TRUE);
}
static void setup(void *myinfo, unsigned int *nfcache) {
MODULE_DATATYPE *info = (void *)((MODULE_ENTRYTYPE *)myinfo)->data;
info->avg = DEFAULT_LIMIT;
info->burst = DEFAULT_BURST;
*nfcache |= NFC_UNKNOWN;
}
static int parse_field(char *field, SV *value, void *myinfo,
unsigned int *nfcache, struct ipt_entry *entry, int *flags) {
MODULE_DATATYPE *info = (void *)(*(MODULE_ENTRYTYPE **)myinfo)->data;
if(!strcmp(field, "limit")) {
if(!parse_rate_sv(value, info)) {
SET_ERRSTR("%s: Unable to parse arg, maybe wrong type?", field);
return(FALSE);
}
}
else if(!strcmp(field, "limit-burst")) {
if(!SvIOK(value)) {
SET_ERRSTR("%s: Arg must be integer", field);
return(FALSE);
}
if (SvIV(value) < 0 || SvIV(value) > 10000) {
SET_ERRSTR("%s: Value out of range", field);
return(FALSE);
}
info->burst = SvIV(value);
}
else
return(FALSE);
return(TRUE);
}
static void get_fields(HV *ent_hash, void *myinfo, struct ipt_entry *entry) {
MODULE_DATATYPE *info = (void *)((MODULE_ENTRYTYPE *)myinfo)->data;
unsigned int i;
for(i = 1; i < (sizeof(rate_list) / sizeof(struct RateList)); i++) {
if(info->avg > rate_list[i].mult || rate_list[i].mult % info->avg != 0)
break;
}
hv_store(ent_hash, "limit", 5,
newSVpvf("%u/%s", rate_list[i-1].mult / info->avg,
rate_list[i-1].name), 0);
hv_store(ent_hash, "limit-burst", 11, newSViv(info->burst), 0);
}
static ModuleDef _module = {
.type = MODULE_TYPE,
.name = MODULE_NAME,
.size = IPT_ALIGN(sizeof(MODULE_DATATYPE)),
.size_uspace = IPT_ALIGN(sizeof(MODULE_DATATYPE)),
.setup = setup,
.parse_field = parse_field,
.get_fields = get_fields,
};
ModuleDef *init(void) {
return(&_module);
}
/* vim: ts=4
*/