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/*
* (C) 2012 Intel Corporation
*
* 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.
*
* Authors:
* Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
*/
#include "internal.h"
#include <stdio.h>
#include <stdint.h>
#include <limits.h>
#include <errno.h>
#include <arpa/inet.h>
#include <libmnl/libmnl.h>
#include <linux/netfilter/nf_tables.h>
#include <libnftables/expr.h>
#include <libnftables/rule.h>
#include "expr_ops.h"
struct nft_expr_nat {
enum nft_registers sreg_addr_min;
enum nft_registers sreg_addr_max;
enum nft_registers sreg_proto_min;
enum nft_registers sreg_proto_max;
int family;
enum nft_nat_types type;
};
static int
nft_rule_expr_nat_set(struct nft_rule_expr *e, uint16_t type,
const void *data, size_t data_len)
{
struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data;
switch(type) {
case NFT_EXPR_NAT_TYPE:
nat->type = *((uint32_t *)data);
break;
case NFT_EXPR_NAT_FAMILY:
nat->family = *((uint32_t *)data);
break;
case NFT_EXPR_NAT_REG_ADDR_MIN:
nat->sreg_addr_min = *((uint32_t *)data);
break;
case NFT_EXPR_NAT_REG_ADDR_MAX:
nat->sreg_addr_max = *((uint32_t *)data);
break;
case NFT_EXPR_NAT_REG_PROTO_MIN:
nat->sreg_proto_min = *((uint32_t *)data);
break;
case NFT_EXPR_NAT_REG_PROTO_MAX:
nat->sreg_proto_max = *((uint32_t *)data);
break;
default:
return -1;
}
return 0;
}
static const void *
nft_rule_expr_nat_get(const struct nft_rule_expr *e, uint16_t type,
size_t *data_len)
{
struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data;
switch(type) {
case NFT_EXPR_NAT_TYPE:
if (e->flags & (1 << NFT_EXPR_NAT_TYPE)) {
*data_len = sizeof(nat->type);
return &nat->type;
}
break;
case NFT_EXPR_NAT_FAMILY:
if (e->flags & (1 << NFT_EXPR_NAT_FAMILY)) {
*data_len = sizeof(nat->family);
return &nat->family;
}
break;
case NFT_EXPR_NAT_REG_ADDR_MIN:
if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MIN)) {
*data_len = sizeof(nat->sreg_addr_min);
return &nat->sreg_addr_min;
}
break;
case NFT_EXPR_NAT_REG_ADDR_MAX:
if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MAX)) {
*data_len = sizeof(nat->sreg_addr_max);
return &nat->sreg_addr_max;
}
break;
case NFT_EXPR_NAT_REG_PROTO_MIN:
if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MIN)) {
*data_len = sizeof(nat->sreg_proto_min);
return &nat->sreg_proto_min;
}
break;
case NFT_EXPR_NAT_REG_PROTO_MAX:
if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MAX)) {
*data_len = sizeof(nat->sreg_proto_max);
return &nat->sreg_proto_max;
}
break;
default:
break;
}
return NULL;
}
static int nft_rule_expr_nat_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_NAT_MAX) < 0)
return MNL_CB_OK;
switch(type) {
case NFTA_NAT_TYPE:
case NFTA_NAT_FAMILY:
case NFTA_NAT_REG_ADDR_MIN:
case NFTA_NAT_REG_ADDR_MAX:
case NFTA_NAT_REG_PROTO_MIN:
case NFTA_NAT_REG_PROTO_MAX:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) {
perror("mnl_attr_validate");
return MNL_CB_ERROR;
}
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static int
nft_rule_expr_nat_parse(struct nft_rule_expr *e, struct nlattr *attr)
{
struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data;
struct nlattr *tb[NFTA_NAT_MAX+1] = {};
if (mnl_attr_parse_nested(attr, nft_rule_expr_nat_cb, tb) < 0)
return -1;
if (tb[NFTA_NAT_TYPE]) {
nat->type = ntohl(mnl_attr_get_u32(tb[NFTA_NAT_TYPE]));
e->flags |= (1 << NFT_EXPR_NAT_TYPE);
}
if (tb[NFTA_NAT_FAMILY]) {
nat->family = ntohl(mnl_attr_get_u32(tb[NFTA_NAT_FAMILY]));
e->flags |= (1 << NFT_EXPR_NAT_FAMILY);
}
if (tb[NFTA_NAT_REG_ADDR_MIN]) {
nat->sreg_addr_min =
ntohl(mnl_attr_get_u32(tb[NFTA_NAT_REG_ADDR_MIN]));
e->flags |= (1 << NFT_EXPR_NAT_REG_ADDR_MIN);
}
if (tb[NFTA_NAT_REG_ADDR_MAX]) {
nat->sreg_addr_max =
ntohl(mnl_attr_get_u32(tb[NFTA_NAT_REG_ADDR_MAX]));
e->flags |= (1 << NFT_EXPR_NAT_REG_ADDR_MAX);
}
if (tb[NFTA_NAT_REG_PROTO_MIN]) {
nat->sreg_proto_min =
ntohl(mnl_attr_get_u32(tb[NFTA_NAT_REG_PROTO_MIN]));
e->flags |= (1 << NFT_EXPR_NAT_REG_PROTO_MIN);
}
if (tb[NFTA_NAT_REG_PROTO_MAX]) {
nat->sreg_proto_max =
ntohl(mnl_attr_get_u32(tb[NFTA_NAT_REG_PROTO_MAX]));
e->flags |= (1 << NFT_EXPR_NAT_REG_PROTO_MAX);
}
return 0;
}
static void
nft_rule_expr_nat_build(struct nlmsghdr *nlh, struct nft_rule_expr *e)
{
struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data;
if (e->flags & (1 << NFT_EXPR_NAT_TYPE))
mnl_attr_put_u32(nlh, NFTA_NAT_TYPE, htonl(nat->type));
if (e->flags & (1 << NFT_EXPR_NAT_FAMILY))
mnl_attr_put_u32(nlh, NFTA_NAT_FAMILY, htonl(nat->family));
if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MIN))
mnl_attr_put_u32(nlh, NFTA_NAT_REG_ADDR_MIN,
htonl(nat->sreg_addr_min));
if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MAX))
mnl_attr_put_u32(nlh, NFTA_NAT_REG_ADDR_MAX,
htonl(nat->sreg_addr_max));
if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MIN))
mnl_attr_put_u32(nlh, NFTA_NAT_REG_PROTO_MIN,
htonl(nat->sreg_proto_min));
if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MAX))
mnl_attr_put_u32(nlh, NFTA_NAT_REG_PROTO_MAX,
htonl(nat->sreg_proto_max));
}
static int nft_rule_expr_nat_xml_parse(struct nft_rule_expr *e, char *xml)
{
#ifdef XML_PARSING
struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data;
mxml_node_t *tree = NULL;
mxml_node_t *node = NULL;
uint64_t tmp;
char *endptr;
int family;
tree = mxmlLoadString(NULL, xml, MXML_OPAQUE_CALLBACK);
if (tree == NULL)
return -1;
if (mxmlElementGetAttr(tree, "type") == NULL) {
mxmlDelete(tree);
return -1;
}
if (strcmp("nat", mxmlElementGetAttr(tree, "type")) != 0) {
mxmlDelete(tree);
return -1;
}
/* Get and set <nat_type>. Mandatory */
node = mxmlFindElement(tree, tree, "nat_type", NULL, NULL,
MXML_DESCEND_FIRST);
if (node == NULL) {
mxmlDelete(tree);
return -1;
}
if (strcmp(node->child->value.opaque, "snat") == 0) {
nat->type = NFT_NAT_SNAT;
} else if (strcmp(node->child->value.opaque, "dnat") == 0) {
nat->type = NFT_NAT_DNAT;
} else {
mxmlDelete(tree);
return -1;
}
e->flags |= (1 << NFT_EXPR_NAT_TYPE);
/* Get and set <family>. Mandatory */
node = mxmlFindElement(tree, tree, "family", NULL, NULL,
MXML_DESCEND);
if (node == NULL) {
mxmlDelete(tree);
return -1;
}
family = nft_str2family(node->child->value.opaque);
if (family < 0) {
mxmlDelete(tree);
return -1;
}
nat->family = family;
e->flags |= (1 << NFT_EXPR_NAT_FAMILY);
/* Get and set <sreg_addr_min>. Not mandatory */
node = mxmlFindElement(tree, tree, "sreg_addr_min", NULL, NULL,
MXML_DESCEND);
if (node != NULL) {
tmp = strtoull(node->child->value.opaque, &endptr, 10);
if (tmp > UINT32_MAX || tmp < 0 || *endptr) {
mxmlDelete(tree);
return -1;
}
nat->sreg_addr_min = (uint32_t)tmp;
e->flags |= (1 << NFT_EXPR_NAT_REG_ADDR_MIN);
}
/* Get and set <sreg_addr_max>. Not mandatory */
node = mxmlFindElement(tree, tree, "sreg_addr_max", NULL, NULL,
MXML_DESCEND);
if (node != NULL) {
tmp = strtoull(node->child->value.opaque, &endptr, 10);
if (tmp > UINT32_MAX || tmp < 0 || *endptr) {
mxmlDelete(tree);
return -1;
}
nat->sreg_addr_max = (uint32_t)tmp;
e->flags |= (1 << NFT_EXPR_NAT_REG_ADDR_MAX);
}
/* Get and set <sreg_proto_min>. Not mandatory */
node = mxmlFindElement(tree, tree, "sreg_proto_min", NULL, NULL,
MXML_DESCEND);
if (node != NULL) {
tmp = strtoull(node->child->value.opaque, &endptr, 10);
if (tmp > UINT32_MAX || tmp < 0 || *endptr) {
mxmlDelete(tree);
return -1;
}
nat->sreg_proto_min = (uint32_t)tmp;
e->flags |= (1 << NFT_EXPR_NAT_REG_PROTO_MIN);
}
/* Get and set <sreg_proto_max>. Not mandatory */
node = mxmlFindElement(tree, tree, "sreg_proto_max", NULL, NULL,
MXML_DESCEND);
if (node != NULL) {
tmp = strtoull(node->child->value.opaque, &endptr, 10);
if (tmp > UINT32_MAX || tmp < 0 || *endptr) {
mxmlDelete(tree);
return -1;
}
nat->sreg_proto_max = (uint32_t)tmp;
e->flags |= (1 << NFT_EXPR_NAT_REG_PROTO_MAX);
}
mxmlDelete(tree);
return 0;
#else
errno = EOPNOTSUPP;
return -1;
#endif
}
static int
nft_rule_expr_nat_snprintf_json(char *buf, size_t size,
struct nft_rule_expr *e)
{
struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data;
int len = size, offset = 0, ret = 0;
if (nat->type == NFT_NAT_SNAT)
ret = snprintf(buf, len, "\"nat_type\" : \"snat\", ");
else if (nat->type == NFT_NAT_DNAT)
ret = snprintf(buf, len, "\nat_type\" : \"dnat\", ");
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
ret = snprintf(buf+offset, len, "\"family\" : \"%s\", ",
nft_family2str(nat->family));
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MIN)) {
ret = snprintf(buf+offset, len,
"\"sreg_addr_min\" : %u, "
"\"sreg_addr_max\" : %u, ",
nat->sreg_addr_min, nat->sreg_addr_max);
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
}
if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MIN)) {
ret = snprintf(buf+offset, len,
"\"sreg_proto_min\" : %u, "
"\"sreg_proto_max\" : %u",
nat->sreg_proto_min, nat->sreg_proto_max);
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
}
return offset;
}
static int
nft_rule_expr_nat_snprintf_xml(char *buf, size_t size,
struct nft_rule_expr *e)
{
struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data;
int len = size, offset = 0, ret = 0;
/* Is a mandatory element. Provide a default, even empty */
if (nat->type == NFT_NAT_SNAT)
ret = snprintf(buf, len, "<nat_type>snat</nat_type>");
else if (nat->type == NFT_NAT_DNAT)
ret = snprintf(buf, len, "<nat_type>dnat</nat_type>");
else
ret = snprintf(buf, len, "<type>unknown</type>");
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
ret = snprintf(buf+offset, len, "<family>%s</family>",
nft_family2str(nat->family));
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MIN)) {
ret = snprintf(buf+offset, len,
"<sreg_addr_min>%u</sreg_addr_min>"
"<sreg_addr_max>%u</sreg_addr_max>",
nat->sreg_addr_min, nat->sreg_addr_max);
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
}
if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MIN)) {
ret = snprintf(buf+offset, len,
"<sreg_proto_min>%u</sreg_proto_min>"
"<sreg_proto_max>%u</sreg_proto_max>",
nat->sreg_proto_min, nat->sreg_proto_max);
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
}
return offset;
}
static int
nft_rule_expr_nat_snprintf_default(char *buf, size_t size,
struct nft_rule_expr *e)
{
struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data;
int len = size, offset = 0, ret = 0;
switch (nat->type) {
case NFT_NAT_SNAT:
ret = snprintf(buf, len, "type=NFT_NAT_SNAT ");
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
break;
case NFT_NAT_DNAT:
ret = snprintf(buf, len, "type=NFT_NAT_DNAT ");
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
break;
}
ret = snprintf(buf+offset, len, "family=%s ", nft_family2str(nat->family));
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MIN)) {
ret = snprintf(buf+offset, len,
"sreg_addr_min_v4=%u sreg_addr_max_v4=%u ",
nat->sreg_addr_min, nat->sreg_addr_max);
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
}
if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MIN)) {
ret = snprintf(buf+offset, len,
"sreg_proto_min=%u sreg_proto_max=%u ",
nat->sreg_proto_min, nat->sreg_proto_max);
SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
}
return offset;
}
static int
nft_rule_expr_nat_snprintf(char *buf, size_t size, uint32_t type,
uint32_t flags, struct nft_rule_expr *e)
{
switch (type) {
case NFT_RULE_O_DEFAULT:
return nft_rule_expr_nat_snprintf_default(buf, size, e);
case NFT_RULE_O_XML:
return nft_rule_expr_nat_snprintf_xml(buf, size, e);
case NFT_RULE_O_JSON:
return nft_rule_expr_nat_snprintf_json(buf, size, e);
default:
break;
}
return -1;
}
struct expr_ops expr_ops_nat = {
.name = "nat",
.alloc_len = sizeof(struct nft_expr_nat),
.max_attr = NFTA_NAT_MAX,
.set = nft_rule_expr_nat_set,
.get = nft_rule_expr_nat_get,
.parse = nft_rule_expr_nat_parse,
.build = nft_rule_expr_nat_build,
.snprintf = nft_rule_expr_nat_snprintf,
.xml_parse = nft_rule_expr_nat_xml_parse,
};
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