connlimit.c
/*
* (C) 2018 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.
*/
#include <stdio.h>
#include <stdint.h>
#include <arpa/inet.h>
#include <errno.h>
#include <inttypes.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_connlimit {
uint32_t count;
uint32_t flags;
};
static int
nftnl_expr_connlimit_set(struct nftnl_expr *e, uint16_t type,
const void *data, uint32_t data_len)
{
struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_CONNLIMIT_COUNT:
memcpy(&connlimit->count, data, sizeof(connlimit->count));
break;
case NFTNL_EXPR_CONNLIMIT_FLAGS:
memcpy(&connlimit->flags, data, sizeof(connlimit->flags));
break;
default:
return -1;
}
return 0;
}
static const void *
nftnl_expr_connlimit_get(const struct nftnl_expr *e, uint16_t type,
uint32_t *data_len)
{
struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_CONNLIMIT_COUNT:
*data_len = sizeof(connlimit->count);
return &connlimit->count;
case NFTNL_EXPR_CONNLIMIT_FLAGS:
*data_len = sizeof(connlimit->flags);
return &connlimit->flags;
}
return NULL;
}
static int nftnl_expr_connlimit_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_CONNLIMIT_MAX) < 0)
return MNL_CB_OK;
switch(type) {
case NFTA_CONNLIMIT_COUNT:
case NFTA_CONNLIMIT_FLAGS:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
abi_breakage();
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static void
nftnl_expr_connlimit_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
{
struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
if (e->flags & (1 << NFTNL_EXPR_CONNLIMIT_COUNT))
mnl_attr_put_u32(nlh, NFTA_CONNLIMIT_COUNT,
htonl(connlimit->count));
if (e->flags & (1 << NFTNL_EXPR_CONNLIMIT_FLAGS))
mnl_attr_put_u32(nlh, NFTA_CONNLIMIT_FLAGS,
htonl(connlimit->flags));
}
static int
nftnl_expr_connlimit_parse(struct nftnl_expr *e, struct nlattr *attr)
{
struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
struct nlattr *tb[NFTA_CONNLIMIT_MAX+1] = {};
if (mnl_attr_parse_nested(attr, nftnl_expr_connlimit_cb, tb) < 0)
return -1;
if (tb[NFTA_CONNLIMIT_COUNT]) {
connlimit->count =
ntohl(mnl_attr_get_u32(tb[NFTA_CONNLIMIT_COUNT]));
e->flags |= (1 << NFTNL_EXPR_CONNLIMIT_COUNT);
}
if (tb[NFTA_CONNLIMIT_FLAGS]) {
connlimit->flags =
ntohl(mnl_attr_get_u32(tb[NFTA_CONNLIMIT_FLAGS]));
e->flags |= (1 << NFTNL_EXPR_CONNLIMIT_FLAGS);
}
return 0;
}
static int nftnl_expr_connlimit_snprintf_default(char *buf, size_t len,
const struct nftnl_expr *e)
{
struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
return snprintf(buf, len, "count %u flags %x ",
connlimit->count, connlimit->flags);
}
static int nftnl_expr_connlimit_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_connlimit_snprintf_default(buf, len, e);
case NFTNL_OUTPUT_XML:
case NFTNL_OUTPUT_JSON:
default:
break;
}
return -1;
}
struct expr_ops expr_ops_connlimit = {
.name = "connlimit",
.alloc_len = sizeof(struct nftnl_expr_connlimit),
.max_attr = NFTA_CONNLIMIT_MAX,
.set = nftnl_expr_connlimit_set,
.get = nftnl_expr_connlimit_get,
.parse = nftnl_expr_connlimit_parse,
.build = nftnl_expr_connlimit_build,
.snprintf = nftnl_expr_connlimit_snprintf,
};
nftnl_expr_connlimit
Definition: connlimit.c:23