expr/limit.c
/*
* (C) 2012-2013 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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.
*
* This code has been sponsored by Sophos Astaro <http://www.sophos.com>
*/
#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <string.h>
#include <arpa/inet.h>
#include <errno.h>
#include <linux/netfilter/nf_tables.h>
#include "internal.h"
#include <libmnl/libmnl.h>
#include <libnftnl/expr.h>
#include <libnftnl/rule.h>
struct nftnl_expr_limit {
uint64_t rate;
uint64_t unit;
uint32_t burst;
enum nft_limit_type type;
uint32_t flags;
};
static int
nftnl_expr_limit_set(struct nftnl_expr *e, uint16_t type,
const void *data, uint32_t data_len)
{
struct nftnl_expr_limit *limit = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_LIMIT_RATE:
memcpy(&limit->rate, data, sizeof(limit->rate));
break;
case NFTNL_EXPR_LIMIT_UNIT:
memcpy(&limit->unit, data, sizeof(limit->unit));
break;
case NFTNL_EXPR_LIMIT_BURST:
memcpy(&limit->burst, data, sizeof(limit->burst));
break;
case NFTNL_EXPR_LIMIT_TYPE:
memcpy(&limit->type, data, sizeof(limit->type));
break;
case NFTNL_EXPR_LIMIT_FLAGS:
memcpy(&limit->flags, data, sizeof(limit->flags));
break;
default:
return -1;
}
return 0;
}
static const void *
nftnl_expr_limit_get(const struct nftnl_expr *e, uint16_t type,
uint32_t *data_len)
{
struct nftnl_expr_limit *limit = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_LIMIT_RATE:
*data_len = sizeof(uint64_t);
return &limit->rate;
case NFTNL_EXPR_LIMIT_UNIT:
*data_len = sizeof(uint64_t);
return &limit->unit;
case NFTNL_EXPR_LIMIT_BURST:
*data_len = sizeof(uint32_t);
return &limit->burst;
case NFTNL_EXPR_LIMIT_TYPE:
*data_len = sizeof(uint32_t);
return &limit->type;
case NFTNL_EXPR_LIMIT_FLAGS:
*data_len = sizeof(uint32_t);
return &limit->flags;
}
return NULL;
}
static int nftnl_expr_limit_cb(const struct nlattr *attr, void *data)
{
const struct nlattr **tb = data;
int type = mnl_attr_get_type(attr);
if (mnl_attr_type_valid(attr, NFTA_LIMIT_MAX) < 0)
return MNL_CB_OK;
switch(type) {
case NFTA_LIMIT_RATE:
case NFTA_LIMIT_UNIT:
if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
abi_breakage();
break;
case NFTA_LIMIT_BURST:
case NFTA_LIMIT_TYPE:
case NFTA_LIMIT_FLAGS:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
abi_breakage();
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static void
nftnl_expr_limit_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
{
struct nftnl_expr_limit *limit = nftnl_expr_data(e);
if (e->flags & (1 << NFTNL_EXPR_LIMIT_RATE))
mnl_attr_put_u64(nlh, NFTA_LIMIT_RATE, htobe64(limit->rate));
if (e->flags & (1 << NFTNL_EXPR_LIMIT_UNIT))
mnl_attr_put_u64(nlh, NFTA_LIMIT_UNIT, htobe64(limit->unit));
if (e->flags & (1 << NFTNL_EXPR_LIMIT_BURST))
mnl_attr_put_u32(nlh, NFTA_LIMIT_BURST, htonl(limit->burst));
if (e->flags & (1 << NFTNL_EXPR_LIMIT_TYPE))
mnl_attr_put_u32(nlh, NFTA_LIMIT_TYPE, htonl(limit->type));
if (e->flags & (1 << NFTNL_EXPR_LIMIT_FLAGS))
mnl_attr_put_u32(nlh, NFTA_LIMIT_FLAGS, htonl(limit->flags));
}
static int
nftnl_expr_limit_parse(struct nftnl_expr *e, struct nlattr *attr)
{
struct nftnl_expr_limit *limit = nftnl_expr_data(e);
struct nlattr *tb[NFTA_LIMIT_MAX+1] = {};
if (mnl_attr_parse_nested(attr, nftnl_expr_limit_cb, tb) < 0)
return -1;
if (tb[NFTA_LIMIT_RATE]) {
limit->rate = be64toh(mnl_attr_get_u64(tb[NFTA_LIMIT_RATE]));
e->flags |= (1 << NFTNL_EXPR_LIMIT_RATE);
}
if (tb[NFTA_LIMIT_UNIT]) {
limit->unit = be64toh(mnl_attr_get_u64(tb[NFTA_LIMIT_UNIT]));
e->flags |= (1 << NFTNL_EXPR_LIMIT_UNIT);
}
if (tb[NFTA_LIMIT_BURST]) {
limit->burst = ntohl(mnl_attr_get_u32(tb[NFTA_LIMIT_BURST]));
e->flags |= (1 << NFTNL_EXPR_LIMIT_BURST);
}
if (tb[NFTA_LIMIT_TYPE]) {
limit->type = ntohl(mnl_attr_get_u32(tb[NFTA_LIMIT_TYPE]));
e->flags |= (1 << NFTNL_EXPR_LIMIT_TYPE);
}
if (tb[NFTA_LIMIT_FLAGS]) {
limit->flags = ntohl(mnl_attr_get_u32(tb[NFTA_LIMIT_FLAGS]));
e->flags |= (1 << NFTNL_EXPR_LIMIT_FLAGS);
}
return 0;
}
static const char *get_unit(uint64_t u)
{
switch (u) {
case 1: return "second";
case 60: return "minute";
case 60 * 60: return "hour";
case 60 * 60 * 24: return "day";
case 60 * 60 * 24 * 7: return "week";
}
return "error";
}
static const char *limit_to_type(enum nft_limit_type type)
{
switch (type) {
default:
case NFT_LIMIT_PKTS:
return "packets";
case NFT_LIMIT_PKT_BYTES:
return "bytes";
}
}
static int nftnl_expr_limit_snprintf_default(char *buf, size_t len,
const struct nftnl_expr *e)
{
struct nftnl_expr_limit *limit = nftnl_expr_data(e);
return snprintf(buf, len, "rate %"PRIu64"/%s burst %u type %s flags 0x%x ",
limit->rate, get_unit(limit->unit), limit->burst,
limit_to_type(limit->type), limit->flags);
}
static int
nftnl_expr_limit_snprintf(char *buf, size_t len, uint32_t type,
uint32_t flags, const struct nftnl_expr *e)
{
switch(type) {
case NFTNL_OUTPUT_DEFAULT:
return nftnl_expr_limit_snprintf_default(buf, len, e);
case NFTNL_OUTPUT_XML:
case NFTNL_OUTPUT_JSON:
default:
break;
}
return -1;
}
struct expr_ops expr_ops_limit = {
.name = "limit",
.alloc_len = sizeof(struct nftnl_expr_limit),
.max_attr = NFTA_LIMIT_MAX,
.set = nftnl_expr_limit_set,
.get = nftnl_expr_limit_get,
.parse = nftnl_expr_limit_parse,
.build = nftnl_expr_limit_build,
.snprintf = nftnl_expr_limit_snprintf,
};
nftnl_expr_limit
Definition: expr/limit.c:25