incubator-nuttx/net/nat/nat.h

405 lines
14 KiB
C

/****************************************************************************
* net/nat/nat.h
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
#ifndef __NET_NAT_NAT_H
#define __NET_NAT_NAT_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdbool.h>
#include <stdint.h>
#include <netinet/in.h>
#include <nuttx/hashtable.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/netdev.h>
#ifdef CONFIG_NET_NAT
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Adjust checksums in headers. */
#define nat_chksum_adjust(chksum,optr,nptr,len) \
net_chksum_adjust((FAR uint16_t *)(chksum), (FAR uint16_t *)(optr), len, \
(FAR uint16_t *)(nptr), len)
/* Getting IP & Port to manipulate from L3/L4 header. */
#define MANIP_IPADDR(iphdr,manip_type) \
((manip_type) == NAT_MANIP_SRC ? (iphdr)->srcipaddr : (iphdr)->destipaddr)
#define MANIP_PORT(l4hdr,manip_type) \
((manip_type) == NAT_MANIP_SRC ? &(l4hdr)->srcport : &(l4hdr)->destport)
/* Getting peer IP & Port (just other than MANIP) */
#define PEER_IPADDR(iphdr,manip_type) \
((manip_type) != NAT_MANIP_SRC ? (iphdr)->srcipaddr : (iphdr)->destipaddr)
#define PEER_PORT(l4hdr,manip_type) \
((manip_type) != NAT_MANIP_SRC ? &(l4hdr)->srcport : &(l4hdr)->destport)
/****************************************************************************
* Public Types
****************************************************************************/
struct ipv4_nat_entry_s
{
hash_node_t hash_inbound;
hash_node_t hash_outbound;
/* Local Network External Network
* |----------------|
* <local IP, | | <external IP, <peer IP,
* -----------| |-----------------------------
* local port> | | external port> peer port>
* |----------------|
*
* Full cone NAT only need to save local ip:port and external ip:port.
* Symmetric NAT need to save peer ip:port as well.
* For ICMP, save id in port field.
*/
in_addr_t local_ip; /* IP address of the local (private) host. */
in_addr_t external_ip; /* External IP address. */
#ifdef CONFIG_NET_NAT44_SYMMETRIC
in_addr_t peer_ip; /* Peer IP address. */
#endif
uint16_t local_port; /* Port of the local (private) host. */
uint16_t external_port; /* The external port of local (private) host. */
#ifdef CONFIG_NET_NAT44_SYMMETRIC
uint16_t peer_port; /* Peer port. */
#endif
uint8_t protocol; /* L4 protocol (TCP, UDP etc). */
int32_t expire_time; /* The expiration time of this entry. */
};
struct ipv6_nat_entry_s
{
hash_node_t hash_inbound;
hash_node_t hash_outbound;
net_ipv6addr_t local_ip; /* IP address of the local host. */
net_ipv6addr_t external_ip; /* External IP address. */
#ifdef CONFIG_NET_NAT66_SYMMETRIC
net_ipv6addr_t peer_ip; /* Peer IP address. */
#endif
uint16_t local_port; /* Port of the local host. */
uint16_t external_port; /* The external port of local host. */
#ifdef CONFIG_NET_NAT66_SYMMETRIC
uint16_t peer_port; /* Peer port. */
#endif
uint8_t protocol; /* L4 protocol (TCP, UDP etc). */
int32_t expire_time; /* The expiration time of this entry. */
};
typedef struct ipv4_nat_entry_s ipv4_nat_entry_t;
typedef struct ipv6_nat_entry_s ipv6_nat_entry_t;
typedef CODE void (*ipv4_nat_entry_cb_t)(FAR ipv4_nat_entry_t *entry,
FAR void *arg);
typedef CODE void (*ipv6_nat_entry_cb_t)(FAR ipv6_nat_entry_t *entry,
FAR void *arg);
/* NAT IP/Port manipulate type, to indicate whether to manipulate source or
* destination IP/Port in a packet.
*/
enum nat_manip_type_e
{
NAT_MANIP_SRC,
NAT_MANIP_DST
};
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: nat_enable
*
* Description:
* Enable NAT function on a network device.
*
* Input Parameters:
* dev - The device on which the outbound packets will be masqueraded.
*
* Returned Value:
* Zero is returned if NAT function is successfully enabled on the device;
* A negated errno value is returned if failed.
*
****************************************************************************/
int nat_enable(FAR struct net_driver_s *dev);
/****************************************************************************
* Name: nat_disable
*
* Description:
* Disable NAT function on a network device.
*
* Input Parameters:
* dev - The device on which the NAT function will be disabled.
*
* Returned Value:
* Zero is returned if NAT function is successfully disabled on the device;
* A negated errno value is returned if failed.
*
****************************************************************************/
int nat_disable(FAR struct net_driver_s *dev);
/****************************************************************************
* Name: ipv4/ipv6_nat_inbound
*
* Description:
* Check if a received packet belongs to a NAT entry. If so, translate it.
*
* Input Parameters:
* dev - The device on which the packet is received.
* ipv4/ipv6 - Points to the IP header with dev->d_buf.
*
****************************************************************************/
#ifdef CONFIG_NET_NAT44
void ipv4_nat_inbound(FAR struct net_driver_s *dev,
FAR struct ipv4_hdr_s *ipv4);
#endif
#ifdef CONFIG_NET_NAT66
void ipv6_nat_inbound(FAR struct net_driver_s *dev,
FAR struct ipv6_hdr_s *ipv6);
#endif
/****************************************************************************
* Name: ipv4/ipv6_nat_outbound
*
* Description:
* Check if we want to perform NAT with this outbound packet before sending
* it. If so, translate it.
*
* Input Parameters:
* dev - The device on which the packet will be sent.
* ipv4/ipv6 - Points to the IP header to be filled into dev->d_buf later.
* manip_type - Whether local IP/Port is in source or destination.
*
* Returned Value:
* Zero is returned if NAT is successfully applied, or is not enabled for
* this packet;
* A negated errno value is returned if error occured.
*
****************************************************************************/
#ifdef CONFIG_NET_NAT44
int ipv4_nat_outbound(FAR struct net_driver_s *dev,
FAR struct ipv4_hdr_s *ipv4,
enum nat_manip_type_e manip_type);
#endif
#ifdef CONFIG_NET_NAT66
int ipv6_nat_outbound(FAR struct net_driver_s *dev,
FAR struct ipv6_hdr_s *ipv6,
enum nat_manip_type_e manip_type);
#endif
/****************************************************************************
* Name: nat_port_inuse
*
* Description:
* Check whether a port is currently used by NAT.
*
* Input Parameters:
* domain - The domain of the packet.
* protocol - The L4 protocol of the packet.
* ip - The IP bind with the port (in network byte order).
* port - The port number to check (in network byte order).
*
* Returned Value:
* True if the port is already used by NAT, otherwise false.
*
****************************************************************************/
bool nat_port_inuse(uint8_t domain, uint8_t protocol,
FAR const union ip_addr_u *ip, uint16_t port);
/****************************************************************************
* Name: nat_port_select
*
* Description:
* Select an available port number for TCP/UDP protocol, or id for ICMP.
*
* Input Parameters:
* dev - The device on which the packet will be sent.
* domain - The domain of the packet.
* protocol - The L4 protocol of the packet.
* external_ip - The external IP bind with the port.
* local_port - The local port of the packet, as reference.
*
* Returned Value:
* External port number on success; 0 on failure
*
****************************************************************************/
uint16_t nat_port_select(FAR struct net_driver_s *dev,
uint8_t domain, uint8_t protocol,
FAR const union ip_addr_u *external_ip,
uint16_t local_port);
/****************************************************************************
* Name: nat_expire_time
*
* Description:
* Get the expiration time of a specific protocol.
*
* Input Parameters:
* protocol - The L4 protocol of the packet.
*
* Returned Value:
* The expiration time of the protocol.
*
****************************************************************************/
uint32_t nat_expire_time(uint8_t protocol);
/****************************************************************************
* Name: ipv4/ipv6_nat_entry_foreach
*
* Description:
* Call the callback function for each NAT entry.
*
* Input Parameters:
* cb - The callback function.
* arg - The argument to pass to the callback function.
*
****************************************************************************/
#ifdef CONFIG_NET_NAT44
void ipv4_nat_entry_foreach(ipv4_nat_entry_cb_t cb, FAR void *arg);
#endif
#ifdef CONFIG_NET_NAT66
void ipv6_nat_entry_foreach(ipv6_nat_entry_cb_t cb, FAR void *arg);
#endif
/****************************************************************************
* Name: ipv4/ipv6_nat_entry_clear
*
* Description:
* Clear all entries related to dev. Called when NAT will be disabled on
* any device.
*
* Input Parameters:
* dev - The device on which NAT entries will be cleared.
*
* Assumptions:
* NAT is initialized.
*
****************************************************************************/
#ifdef CONFIG_NET_NAT44
void ipv4_nat_entry_clear(FAR struct net_driver_s *dev);
#endif
#ifdef CONFIG_NET_NAT66
void ipv6_nat_entry_clear(FAR struct net_driver_s *dev);
#endif
/****************************************************************************
* Name: ipv4/ipv6_nat_inbound_entry_find
*
* Description:
* Find the inbound entry in NAT entry list.
*
* Input Parameters:
* protocol - The L4 protocol of the packet.
* external_ip - The external ip of the packet, supports INADDR_ANY.
* external_port - The external port of the packet.
* peer_ip - The peer ip of the packet.
* peer_port - The peer port of the packet.
* refresh - Whether to refresh the selected entry.
*
* Returned Value:
* Pointer to entry on success; null on failure
*
****************************************************************************/
#ifdef CONFIG_NET_NAT44
FAR ipv4_nat_entry_t *
ipv4_nat_inbound_entry_find(uint8_t protocol, in_addr_t external_ip,
uint16_t external_port, in_addr_t peer_ip,
uint16_t peer_port, bool refresh);
#endif
#ifdef CONFIG_NET_NAT66
FAR ipv6_nat_entry_t *
ipv6_nat_inbound_entry_find(uint8_t protocol,
const net_ipv6addr_t external_ip,
uint16_t external_port,
const net_ipv6addr_t peer_ip,
uint16_t peer_port, bool refresh);
#endif
/****************************************************************************
* Name: ipv4/ipv6_nat_outbound_entry_find
*
* Description:
* Find the outbound entry in NAT entry list. Create one if corresponding
* entry does not exist.
*
* Input Parameters:
* dev - The device on which the packet will be sent.
* protocol - The L4 protocol of the packet.
* local_ip - The local ip of the packet.
* local_port - The local port of the packet.
* peer_ip - The peer ip of the packet.
* peer_port - The peer port of the packet.
* try_create - Try create the entry if no entry found.
*
* Returned Value:
* Pointer to entry on success; null on failure
*
****************************************************************************/
#ifdef CONFIG_NET_NAT44
FAR ipv4_nat_entry_t *
ipv4_nat_outbound_entry_find(FAR struct net_driver_s *dev, uint8_t protocol,
in_addr_t local_ip, uint16_t local_port,
in_addr_t peer_ip, uint16_t peer_port,
bool try_create);
#endif
#ifdef CONFIG_NET_NAT66
FAR ipv6_nat_entry_t *
ipv6_nat_outbound_entry_find(FAR struct net_driver_s *dev, uint8_t protocol,
const net_ipv6addr_t local_ip,
uint16_t local_port,
const net_ipv6addr_t peer_ip,
uint16_t peer_port, bool try_create);
#endif
#endif /* CONFIG_NET_NAT */
#endif /* __NET_NAT_NAT_H */