xfrm.c
/*
* 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 <string.h>
#include <stdint.h>
#include <arpa/inet.h>
#include <errno.h>
#include <linux/netfilter/nf_tables.h>
#include <linux/xfrm.h>
#include "internal.h"
#include <libmnl/libmnl.h>
#include <libnftnl/expr.h>
#include <libnftnl/rule.h>
struct nftnl_expr_xfrm {
enum nft_registers dreg;
enum nft_xfrm_keys key;
uint32_t spnum;
uint8_t dir;
};
static int
nftnl_expr_xfrm_set(struct nftnl_expr *e, uint16_t type,
const void *data, uint32_t data_len)
{
struct nftnl_expr_xfrm *x = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_XFRM_KEY:
memcpy(&x->key, data, sizeof(x->key));
break;
case NFTNL_EXPR_XFRM_DIR:
memcpy(&x->dir, data, sizeof(x->dir));
break;
case NFTNL_EXPR_XFRM_SPNUM:
memcpy(&x->spnum, data, sizeof(x->spnum));
break;
case NFTNL_EXPR_XFRM_DREG:
memcpy(&x->dreg, data, sizeof(x->dreg));
break;
default:
return -1;
}
return 0;
}
static const void *
nftnl_expr_xfrm_get(const struct nftnl_expr *e, uint16_t type,
uint32_t *data_len)
{
struct nftnl_expr_xfrm *x = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_XFRM_KEY:
*data_len = sizeof(x->key);
return &x->key;
case NFTNL_EXPR_XFRM_DIR:
*data_len = sizeof(x->dir);
return &x->dir;
case NFTNL_EXPR_XFRM_SPNUM:
*data_len = sizeof(x->spnum);
return &x->spnum;
case NFTNL_EXPR_XFRM_DREG:
*data_len = sizeof(x->dreg);
return &x->dreg;
}
return NULL;
}
static int nftnl_expr_xfrm_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_XFRM_MAX) < 0)
return MNL_CB_OK;
switch (type) {
case NFTA_XFRM_DREG:
case NFTA_XFRM_KEY:
case NFTA_XFRM_SPNUM:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
abi_breakage();
break;
case NFTA_XFRM_DIR:
if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0)
abi_breakage();
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static void
nftnl_expr_xfrm_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
{
struct nftnl_expr_xfrm *x = nftnl_expr_data(e);
if (e->flags & (1 << NFTNL_EXPR_XFRM_KEY))
mnl_attr_put_u32(nlh, NFTA_XFRM_KEY, htonl(x->key));
if (e->flags & (1 << NFTNL_EXPR_XFRM_DIR))
mnl_attr_put_u8(nlh, NFTA_XFRM_DIR, x->dir);
if (e->flags & (1 << NFTNL_EXPR_XFRM_SPNUM))
mnl_attr_put_u32(nlh, NFTA_XFRM_SPNUM, htonl(x->spnum));
if (e->flags & (1 << NFTNL_EXPR_XFRM_DREG))
mnl_attr_put_u32(nlh, NFTA_XFRM_DREG, htonl(x->dreg));
}
static int
nftnl_expr_xfrm_parse(struct nftnl_expr *e, struct nlattr *attr)
{
struct nftnl_expr_xfrm *x = nftnl_expr_data(e);
struct nlattr *tb[NFTA_XFRM_MAX+1] = {};
if (mnl_attr_parse_nested(attr, nftnl_expr_xfrm_cb, tb) < 0)
return -1;
if (tb[NFTA_XFRM_KEY]) {
x->key = ntohl(mnl_attr_get_u32(tb[NFTA_XFRM_KEY]));
e->flags |= (1 << NFTNL_EXPR_XFRM_KEY);
}
if (tb[NFTA_XFRM_DIR]) {
x->dir = mnl_attr_get_u8(tb[NFTA_XFRM_DIR]);
e->flags |= (1 << NFTNL_EXPR_XFRM_DIR);
}
if (tb[NFTA_XFRM_SPNUM]) {
x->spnum = ntohl(mnl_attr_get_u32(tb[NFTA_XFRM_SPNUM]));
e->flags |= (1 << NFTNL_EXPR_XFRM_SPNUM);
}
if (tb[NFTA_XFRM_DREG]) {
x->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_XFRM_DREG]));
e->flags |= (1 << NFTNL_EXPR_XFRM_DREG);
}
return 0;
}
static const char *xfrmkey2str_array[] = {
[NFT_XFRM_KEY_DADDR_IP4] = "daddr4",
[NFT_XFRM_KEY_SADDR_IP4] = "saddr4",
[NFT_XFRM_KEY_DADDR_IP6] = "daddr6",
[NFT_XFRM_KEY_SADDR_IP6] = "saddr6",
[NFT_XFRM_KEY_REQID] = "reqid",
[NFT_XFRM_KEY_SPI] = "spi",
};
static const char *xfrmkey2str(uint32_t key)
{
if (key >= sizeof(xfrmkey2str_array) / sizeof(xfrmkey2str_array[0]))
return "unknown";
return xfrmkey2str_array[key];
}
static const char *xfrmdir2str_array[] = {
[XFRM_POLICY_IN] = "in",
[XFRM_POLICY_OUT] = "out",
};
static const char *xfrmdir2str(uint8_t dir)
{
if (dir >= sizeof(xfrmdir2str_array) / sizeof(xfrmdir2str_array[0]))
return "unknown";
return xfrmdir2str_array[dir];
}
#ifdef JSON_PARSING
static uint32_t str2xfrmkey(const char *s)
{
int i;
for (i = 0;
i < sizeof(xfrmkey2str_array) / sizeof(xfrmkey2str_array[0]);
i++) {
if (strcmp(xfrmkey2str_array[i], s) == 0)
return i;
}
return -1;
}
static int str2xfmrdir(const char *s)
{
int i;
for (i = 0;
i < sizeof(xfrmdir2str_array) / sizeof(xfrmdir2str_array[0]);
i++) {
if (strcmp(xfrmkey2str_array[i], s) == 0)
return i;
}
return -1;
}
#endif
static int
nftnl_expr_xfrm_snprintf_default(char *buf, size_t size,
const struct nftnl_expr *e)
{
struct nftnl_expr_xfrm *x = nftnl_expr_data(e);
int ret, remain = size, offset = 0;
if (e->flags & (1 << NFTNL_EXPR_XFRM_DREG)) {
ret = snprintf(buf, remain, "load %s %u %s => reg %u ",
xfrmdir2str(x->dir),
x->spnum,
xfrmkey2str(x->key), x->dreg);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
}
return offset;
}
static int
nftnl_expr_xfrm_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_xfrm_snprintf_default(buf, len, e);
case NFTNL_OUTPUT_XML:
case NFTNL_OUTPUT_JSON:
default:
break;
}
return -1;
}
struct expr_ops expr_ops_xfrm = {
.name = "xfrm",
.alloc_len = sizeof(struct nftnl_expr_xfrm),
.max_attr = NFTA_XFRM_MAX,
.set = nftnl_expr_xfrm_set,
.get = nftnl_expr_xfrm_get,
.parse = nftnl_expr_xfrm_parse,
.build = nftnl_expr_xfrm_build,
.snprintf = nftnl_expr_xfrm_snprintf,
};
nftnl_expr_xfrm
Definition: xfrm.c:21