fwd.c
/*
* (C) 2015 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 <string.h>
#include <arpa/inet.h>
#include <errno.h>
#include "internal.h"
#include <libmnl/libmnl.h>
#include <linux/netfilter/nf_tables.h>
#include <libnftnl/expr.h>
#include <libnftnl/rule.h>
#include "expr_ops.h"
#include "data_reg.h"
struct nftnl_expr_fwd {
enum nft_registers sreg_dev;
enum nft_registers sreg_addr;
uint32_t nfproto;
};
static int nftnl_expr_fwd_set(struct nftnl_expr *e, uint16_t type,
const void *data, uint32_t data_len)
{
struct nftnl_expr_fwd *fwd = nftnl_expr_data(e);
switch (type) {
case NFTNL_EXPR_FWD_SREG_DEV:
memcpy(&fwd->sreg_dev, data, sizeof(fwd->sreg_dev));
break;
case NFTNL_EXPR_FWD_SREG_ADDR:
memcpy(&fwd->sreg_addr, data, sizeof(fwd->sreg_addr));
break;
case NFTNL_EXPR_FWD_NFPROTO:
memcpy(&fwd->nfproto, data, sizeof(fwd->nfproto));
break;
default:
return -1;
}
return 0;
}
static const void *nftnl_expr_fwd_get(const struct nftnl_expr *e,
uint16_t type, uint32_t *data_len)
{
struct nftnl_expr_fwd *fwd = nftnl_expr_data(e);
switch (type) {
case NFTNL_EXPR_FWD_SREG_DEV:
*data_len = sizeof(fwd->sreg_dev);
return &fwd->sreg_dev;
case NFTNL_EXPR_FWD_SREG_ADDR:
*data_len = sizeof(fwd->sreg_addr);
return &fwd->sreg_addr;
case NFTNL_EXPR_FWD_NFPROTO:
*data_len = sizeof(fwd->nfproto);
return &fwd->nfproto;
}
return NULL;
}
static int nftnl_expr_fwd_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_FWD_MAX) < 0)
return MNL_CB_OK;
switch (type) {
case NFTA_FWD_SREG_DEV:
case NFTA_FWD_SREG_ADDR:
case NFTA_FWD_NFPROTO:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
abi_breakage();
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static void nftnl_expr_fwd_build(struct nlmsghdr *nlh,
const struct nftnl_expr *e)
{
struct nftnl_expr_fwd *fwd = nftnl_expr_data(e);
if (e->flags & (1 << NFTNL_EXPR_FWD_SREG_DEV))
mnl_attr_put_u32(nlh, NFTA_FWD_SREG_DEV, htonl(fwd->sreg_dev));
if (e->flags & (1 << NFTNL_EXPR_FWD_SREG_ADDR))
mnl_attr_put_u32(nlh, NFTA_FWD_SREG_ADDR, htonl(fwd->sreg_addr));
if (e->flags & (1 << NFTNL_EXPR_FWD_NFPROTO))
mnl_attr_put_u32(nlh, NFTA_FWD_NFPROTO, htonl(fwd->nfproto));
}
static int nftnl_expr_fwd_parse(struct nftnl_expr *e, struct nlattr *attr)
{
struct nftnl_expr_fwd *fwd = nftnl_expr_data(e);
struct nlattr *tb[NFTA_FWD_MAX + 1] = {};
int ret = 0;
if (mnl_attr_parse_nested(attr, nftnl_expr_fwd_cb, tb) < 0)
return -1;
if (tb[NFTA_FWD_SREG_DEV]) {
fwd->sreg_dev = ntohl(mnl_attr_get_u32(tb[NFTA_FWD_SREG_DEV]));
e->flags |= (1 << NFTNL_EXPR_FWD_SREG_DEV);
}
if (tb[NFTA_FWD_SREG_ADDR]) {
fwd->sreg_addr = ntohl(mnl_attr_get_u32(tb[NFTA_FWD_SREG_ADDR]));
e->flags |= (1 << NFTNL_EXPR_FWD_SREG_ADDR);
}
if (tb[NFTA_FWD_NFPROTO]) {
fwd->nfproto = ntohl(mnl_attr_get_u32(tb[NFTA_FWD_NFPROTO]));
e->flags |= (1 << NFTNL_EXPR_FWD_NFPROTO);
}
return ret;
}
static int nftnl_expr_fwd_snprintf_default(char *buf, size_t len,
const struct nftnl_expr *e,
uint32_t flags)
{
int remain = len, offset = 0, ret;
struct nftnl_expr_fwd *fwd = nftnl_expr_data(e);
if (e->flags & (1 << NFTNL_EXPR_FWD_SREG_DEV)) {
ret = snprintf(buf + offset, remain, "sreg_dev %u ",
fwd->sreg_dev);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
}
if (e->flags & (1 << NFTNL_EXPR_FWD_SREG_ADDR)) {
ret = snprintf(buf + offset, remain, "sreg_addr %u ",
fwd->sreg_addr);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
}
if (e->flags & (1 << NFTNL_EXPR_FWD_NFPROTO)) {
ret = snprintf(buf + offset, remain, "nfproto %u ",
fwd->nfproto);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
}
return offset;
}
static int nftnl_expr_fwd_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_fwd_snprintf_default(buf, len, e, flags);
case NFTNL_OUTPUT_XML:
case NFTNL_OUTPUT_JSON:
default:
break;
}
return -1;
}
struct expr_ops expr_ops_fwd = {
.name = "fwd",
.alloc_len = sizeof(struct nftnl_expr_fwd),
.max_attr = NFTA_FWD_MAX,
.set = nftnl_expr_fwd_set,
.get = nftnl_expr_fwd_get,
.parse = nftnl_expr_fwd_parse,
.build = nftnl_expr_fwd_build,
.snprintf = nftnl_expr_fwd_snprintf,
};
nftnl_expr_fwd
Definition: fwd.c:23