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/*
* (C) 2012 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 <string.h>
#include <arpa/inet.h>
#include <libmnl/libmnl.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <libnftables/expr.h>
#include "expr_ops.h"
#include "data_reg.h"
#include "internal.h"
static int nft_data_parse_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_DATA_MAX) < 0)
return MNL_CB_OK;
switch(type) {
case NFTA_DATA_VALUE:
if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0) {
perror("mnl_attr_validate");
return MNL_CB_ERROR;
}
break;
case NFTA_DATA_VERDICT:
if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0) {
perror("mnl_attr_validate");
return MNL_CB_ERROR;
}
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static int nft_verdict_parse_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_VERDICT_MAX) < 0)
return MNL_CB_OK;
switch(type) {
case NFTA_VERDICT_CODE:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) {
perror("mnl_attr_validate");
return MNL_CB_ERROR;
}
break;
case NFTA_VERDICT_CHAIN:
if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0) {
perror("mnl_attr_validate");
return MNL_CB_ERROR;
}
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static int
nft_parse_verdict(union nft_data_reg *data, const struct nlattr *attr, int *type)
{
struct nlattr *tb[NFTA_VERDICT_MAX+1];
if (mnl_attr_parse_nested(attr, nft_verdict_parse_cb, tb) < 0) {
perror("mnl_attr_parse_nested");
return -1;
}
if (!tb[NFTA_VERDICT_CODE])
return -1;
data->verdict = ntohl(mnl_attr_get_u32(tb[NFTA_VERDICT_CODE]));
switch(data->verdict) {
case NF_ACCEPT:
case NF_DROP:
case NF_QUEUE:
case NFT_CONTINUE:
case NFT_BREAK:
case NFT_RETURN:
if (type)
*type = DATA_VERDICT;
data->len = sizeof(data->verdict);
break;
case NFT_JUMP:
case NFT_GOTO:
if (!tb[NFTA_VERDICT_CHAIN])
return -1;
data->chain = strdup(mnl_attr_get_str(tb[NFTA_VERDICT_CHAIN]));
if (type)
*type = DATA_CHAIN;
break;
default:
return -1;
}
return 0;
}
static int
__nft_parse_data(union nft_data_reg *data, const struct nlattr *attr)
{
void *orig = mnl_attr_get_payload(attr);
size_t data_len = mnl_attr_get_payload_len(attr);
if (data_len == 0)
return -1;
if (data_len > sizeof(uint32_t) * 4)
return -1;
memcpy(data->val, orig, data_len);
data->len = data_len;
return 0;
}
int nft_parse_data(union nft_data_reg *data, struct nlattr *attr, int *type)
{
struct nlattr *tb[NFTA_DATA_MAX+1] = {};
int ret = 0;
if (mnl_attr_parse_nested(attr, nft_data_parse_cb, tb) < 0) {
perror("mnl_attr_parse_nested");
return -1;
}
if (tb[NFTA_DATA_VALUE]) {
if (type)
*type = DATA_VALUE;
ret = __nft_parse_data(data, tb[NFTA_DATA_VALUE]);
if (ret < 0)
return ret;
}
if (tb[NFTA_DATA_VERDICT])
ret = nft_parse_verdict(data, tb[NFTA_DATA_VERDICT], type);
return ret;
}
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