osf.c
#include <stdio.h>
#include <stdint.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>
#define OSF_GENRE_SIZE 32
struct nftnl_expr_osf {
enum nft_registers dreg;
uint8_t ttl;
uint32_t flags;
};
static int nftnl_expr_osf_set(struct nftnl_expr *e, uint16_t type,
const void *data, uint32_t data_len)
{
struct nftnl_expr_osf *osf = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_OSF_DREG:
memcpy(&osf->dreg, data, sizeof(osf->dreg));
break;
case NFTNL_EXPR_OSF_TTL:
memcpy(&osf->ttl, data, sizeof(osf->ttl));
break;
case NFTNL_EXPR_OSF_FLAGS:
memcpy(&osf->flags, data, sizeof(osf->flags));
break;
}
return 0;
}
static const void *
nftnl_expr_osf_get(const struct nftnl_expr *e, uint16_t type,
uint32_t *data_len)
{
struct nftnl_expr_osf *osf = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_OSF_DREG:
*data_len = sizeof(osf->dreg);
return &osf->dreg;
case NFTNL_EXPR_OSF_TTL:
*data_len = sizeof(osf->ttl);
return &osf->ttl;
case NFTNL_EXPR_OSF_FLAGS:
*data_len = sizeof(osf->flags);
return &osf->flags;
}
return NULL;
}
static int nftnl_expr_osf_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_OSF_MAX) < 0)
return MNL_CB_OK;
switch(type) {
case NFTNL_EXPR_OSF_DREG:
case NFTNL_EXPR_OSF_FLAGS:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
abi_breakage();
break;
case NFTNL_EXPR_OSF_TTL:
if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0)
abi_breakage();
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static void
nftnl_expr_osf_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
{
struct nftnl_expr_osf *osf = nftnl_expr_data(e);
if (e->flags & (1 << NFTNL_EXPR_OSF_DREG))
mnl_attr_put_u32(nlh, NFTNL_EXPR_OSF_DREG, htonl(osf->dreg));
if (e->flags & (1 << NFTNL_EXPR_OSF_TTL))
mnl_attr_put_u8(nlh, NFTNL_EXPR_OSF_TTL, osf->ttl);
if (e->flags & (1 << NFTNL_EXPR_OSF_FLAGS))
if (osf->flags)
mnl_attr_put_u32(nlh, NFTNL_EXPR_OSF_FLAGS, htonl(osf->flags));
}
static int
nftnl_expr_osf_parse(struct nftnl_expr *e, struct nlattr *attr)
{
struct nftnl_expr_osf *osf = nftnl_expr_data(e);
struct nlattr *tb[NFTA_OSF_MAX + 1] = {};
if (mnl_attr_parse_nested(attr, nftnl_expr_osf_cb, tb) < 0)
return -1;
if (tb[NFTA_OSF_DREG]) {
osf->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_OSF_DREG]));
e->flags |= (1 << NFTNL_EXPR_OSF_DREG);
}
if (tb[NFTA_OSF_TTL]) {
osf->ttl = mnl_attr_get_u8(tb[NFTA_OSF_TTL]);
e->flags |= (1 << NFTNL_EXPR_OSF_TTL);
}
if (tb[NFTA_OSF_FLAGS]) {
osf->flags = ntohl(mnl_attr_get_u32(tb[NFTA_OSF_FLAGS]));
e->flags |= (1 << NFTNL_EXPR_OSF_FLAGS);
}
return 0;
}
static int nftnl_expr_osf_snprintf_default(char *buf, size_t size,
const struct nftnl_expr *e)
{
struct nftnl_expr_osf *osf = nftnl_expr_data(e);
int ret, offset = 0, len = size;
if (e->flags & (1 << NFTNL_EXPR_OSF_DREG)) {
ret = snprintf(buf, len, "dreg %u ", osf->dreg);
SNPRINTF_BUFFER_SIZE(ret, len, offset);
}
return offset;
}
static int
nftnl_expr_osf_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_osf_snprintf_default(buf, len, e);
case NFTNL_OUTPUT_XML:
case NFTNL_OUTPUT_JSON:
default:
break;
}
return -1;
}
struct expr_ops expr_ops_osf = {
.name = "osf",
.alloc_len = sizeof(struct nftnl_expr_osf),
.max_attr = NFTA_OSF_MAX,
.set = nftnl_expr_osf_set,
.get = nftnl_expr_osf_get,
.parse = nftnl_expr_osf_parse,
.build = nftnl_expr_osf_build,
.snprintf = nftnl_expr_osf_snprintf,
};
nftnl_expr_osf
Definition: osf.c:15