fib.c
/*
* (C) 2016 Red Hat GmbH
* Author: Florian Westphal <fw@strlen.de>
*
* 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 <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_fib {
uint32_t flags;
uint32_t result;
enum nft_registers dreg;
};
static int
nftnl_expr_fib_set(struct nftnl_expr *e, uint16_t result,
const void *data, uint32_t data_len)
{
struct nftnl_expr_fib *fib = nftnl_expr_data(e);
switch (result) {
case NFTNL_EXPR_FIB_RESULT:
memcpy(&fib->result, data, sizeof(fib->result));
break;
case NFTNL_EXPR_FIB_DREG:
memcpy(&fib->dreg, data, sizeof(fib->dreg));
break;
case NFTNL_EXPR_FIB_FLAGS:
memcpy(&fib->flags, data, sizeof(fib->flags));
break;
default:
return -1;
}
return 0;
}
static const void *
nftnl_expr_fib_get(const struct nftnl_expr *e, uint16_t result,
uint32_t *data_len)
{
struct nftnl_expr_fib *fib = nftnl_expr_data(e);
switch (result) {
case NFTNL_EXPR_FIB_RESULT:
*data_len = sizeof(fib->result);
return &fib->result;
case NFTNL_EXPR_FIB_DREG:
*data_len = sizeof(fib->dreg);
return &fib->dreg;
case NFTNL_EXPR_FIB_FLAGS:
*data_len = sizeof(fib->flags);
return &fib->flags;
}
return NULL;
}
static int nftnl_expr_fib_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_FIB_MAX) < 0)
return MNL_CB_OK;
switch (type) {
case NFTA_FIB_RESULT:
case NFTA_FIB_DREG:
case NFTA_FIB_FLAGS:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
abi_breakage();
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static void
nftnl_expr_fib_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
{
struct nftnl_expr_fib *fib = nftnl_expr_data(e);
if (e->flags & (1 << NFTNL_EXPR_FIB_FLAGS))
mnl_attr_put_u32(nlh, NFTA_FIB_FLAGS, htonl(fib->flags));
if (e->flags & (1 << NFTNL_EXPR_FIB_RESULT))
mnl_attr_put_u32(nlh, NFTA_FIB_RESULT, htonl(fib->result));
if (e->flags & (1 << NFTNL_EXPR_FIB_DREG))
mnl_attr_put_u32(nlh, NFTA_FIB_DREG, htonl(fib->dreg));
}
static int
nftnl_expr_fib_parse(struct nftnl_expr *e, struct nlattr *attr)
{
struct nftnl_expr_fib *fib = nftnl_expr_data(e);
struct nlattr *tb[NFTA_FIB_MAX+1] = {};
int ret = 0;
if (mnl_attr_parse_nested(attr, nftnl_expr_fib_cb, tb) < 0)
return -1;
if (tb[NFTA_FIB_RESULT]) {
fib->result = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_RESULT]));
e->flags |= (1 << NFTNL_EXPR_FIB_RESULT);
}
if (tb[NFTA_FIB_DREG]) {
fib->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_DREG]));
e->flags |= (1 << NFTNL_EXPR_FIB_DREG);
}
if (tb[NFTA_FIB_FLAGS]) {
fib->flags = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_FLAGS]));
e->flags |= (1 << NFTNL_EXPR_FIB_FLAGS);
}
return ret;
}
static const char *fib_type[NFT_FIB_RESULT_MAX + 1] = {
[NFT_FIB_RESULT_OIF] = "oif",
[NFT_FIB_RESULT_OIFNAME] = "oifname",
[NFT_FIB_RESULT_ADDRTYPE] = "type",
};
static const char *fib_type_str(enum nft_fib_result r)
{
if (r <= NFT_FIB_RESULT_MAX)
return fib_type[r];
return "unknown";
}
static int
nftnl_expr_fib_snprintf_default(char *buf, size_t size,
const struct nftnl_expr *e)
{
struct nftnl_expr_fib *fib = nftnl_expr_data(e);
int remain = size, offset = 0, ret, i;
uint32_t flags = fib->flags & ~NFTA_FIB_F_PRESENT;
uint32_t present_flag = fib->flags & NFTA_FIB_F_PRESENT;
static const struct {
int bit;
const char *name;
} tab[] = {
{ NFTA_FIB_F_SADDR, "saddr" },
{ NFTA_FIB_F_DADDR, "daddr" },
{ NFTA_FIB_F_MARK, "mark" },
{ NFTA_FIB_F_IIF, "iif" },
{ NFTA_FIB_F_OIF, "oif" },
};
for (i = 0; i < (sizeof(tab) / sizeof(tab[0])); i++) {
if (flags & tab[i].bit) {
ret = snprintf(buf + offset, remain, "%s ",
tab[i].name);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
flags &= ~tab[i].bit;
if (flags) {
ret = snprintf(buf + offset, remain, ". ");
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
}
}
}
if (flags) {
ret = snprintf(buf + offset, remain, "unknown 0x%" PRIx32,
flags);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
}
ret = snprintf(buf + offset, remain, "%s%s => reg %d ",
fib_type_str(fib->result),
present_flag ? " present" : "",
fib->dreg);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
return offset;
}
static int
nftnl_expr_fib_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_fib_snprintf_default(buf, len, e);
case NFTNL_OUTPUT_XML:
case NFTNL_OUTPUT_JSON:
default:
break;
}
return -1;
}
struct expr_ops expr_ops_fib = {
.name = "fib",
.alloc_len = sizeof(struct nftnl_expr_fib),
.max_attr = NFTA_FIB_MAX,
.set = nftnl_expr_fib_set,
.get = nftnl_expr_fib_get,
.parse = nftnl_expr_fib_parse,
.build = nftnl_expr_fib_build,
.snprintf = nftnl_expr_fib_snprintf,
};
nftnl_expr_fib
Definition: fib.c:24