flow_offload.c
#include "internal.h"
#include <stdio.h>
#include <stdint.h>
#include <string.h> /* for memcpy */
#include <arpa/inet.h>
#include <errno.h>
#include <libmnl/libmnl.h>
#include <linux/netfilter/nf_tables.h>
#include <libnftnl/rule.h>
#include <libnftnl/expr.h>
struct nftnl_expr_flow {
char *table_name;
};
static int nftnl_expr_flow_set(struct nftnl_expr *e, uint16_t type,
const void *data, uint32_t data_len)
{
struct nftnl_expr_flow *flow = nftnl_expr_data(e);
switch (type) {
case NFTNL_EXPR_FLOW_TABLE_NAME:
flow->table_name = strdup((const char *)data);
if (!flow->table_name)
return -1;
break;
default:
return -1;
}
return 0;
}
static const void *nftnl_expr_flow_get(const struct nftnl_expr *e,
uint16_t type, uint32_t *data_len)
{
struct nftnl_expr_flow *flow = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_FLOW_TABLE_NAME:
*data_len = strlen(flow->table_name) + 1;
return flow->table_name;
}
return NULL;
}
static int nftnl_expr_flow_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_FLOW_MAX) < 0)
return MNL_CB_OK;
switch(type) {
case NFTA_FLOW_TABLE_NAME:
if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
abi_breakage();
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static void nftnl_expr_flow_build(struct nlmsghdr *nlh,
const struct nftnl_expr *e)
{
struct nftnl_expr_flow *flow = nftnl_expr_data(e);
if (e->flags & (1 << NFTNL_EXPR_FLOW_TABLE_NAME))
mnl_attr_put_strz(nlh, NFTA_FLOW_TABLE_NAME, flow->table_name);
}
static int nftnl_expr_flow_parse(struct nftnl_expr *e, struct nlattr *attr)
{
struct nftnl_expr_flow *flow = nftnl_expr_data(e);
struct nlattr *tb[NFTA_FLOW_MAX+1] = {};
int ret = 0;
if (mnl_attr_parse_nested(attr, nftnl_expr_flow_cb, tb) < 0)
return -1;
if (tb[NFTA_FLOW_TABLE_NAME]) {
flow->table_name =
strdup(mnl_attr_get_str(tb[NFTA_FLOW_TABLE_NAME]));
if (!flow->table_name)
return -1;
e->flags |= (1 << NFTNL_EXPR_FLOW_TABLE_NAME);
}
return ret;
}
static int nftnl_expr_flow_snprintf_default(char *buf, size_t size,
const struct nftnl_expr *e)
{
int remain = size, offset = 0, ret;
struct nftnl_expr_flow *l = nftnl_expr_data(e);
ret = snprintf(buf, remain, "flowtable %s ", l->table_name);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
return offset;
}
static int nftnl_expr_flow_snprintf(char *buf, size_t size, uint32_t type,
uint32_t flags, const struct nftnl_expr *e)
{
switch(type) {
case NFTNL_OUTPUT_DEFAULT:
return nftnl_expr_flow_snprintf_default(buf, size, e);
case NFTNL_OUTPUT_XML:
case NFTNL_OUTPUT_JSON:
default:
break;
}
return -1;
}
static void nftnl_expr_flow_free(const struct nftnl_expr *e)
{
struct nftnl_expr_flow *flow = nftnl_expr_data(e);
xfree(flow->table_name);
}
struct expr_ops expr_ops_flow = {
.name = "flow_offload",
.alloc_len = sizeof(struct nftnl_expr_flow),
.max_attr = NFTA_FLOW_MAX,
.free = nftnl_expr_flow_free,
.set = nftnl_expr_flow_set,
.get = nftnl_expr_flow_get,
.parse = nftnl_expr_flow_parse,
.build = nftnl_expr_flow_build,
.snprintf = nftnl_expr_flow_snprintf,
};
nftnl_expr_flow
Definition: flow_offload.c:13