/* 
   demo_netx_nat.c
 
   This is a small demo of NAT (Network Address Translation) on the high-performance 
   NetX TCP/IP stack.  This demo relies on ThreadX, NetX and NAT APIs to perform network 
   address translation for IP packets traveling between private and external networks.
   this demo concentrates on the ICMP ping operation.
*/

#include   "tx_api.h"
#include   "nx_api.h"    
#include   "nx_nat.h"
                         
extern void    test_control_return(UINT status);
#if defined NX_NAT_ENABLE && defined __PRODUCT_NETXDUO__ && (NX_MAX_PHYSICAL_INTERFACES >= 2)

#define     DEMO_STACK_SIZE         2048
#define     DEMO_DATA               "ABCDEFGHIJKLMNOPQRSTUVWXYZ "
                                                 
/* Define the ThreadX and NetX object control blocks...  */

static TX_THREAD                    ntest_0;

/* Set up the NAT components. */

/* Create a NAT instance, packet pool and translation table. */

NX_NAT_DEVICE                       nat_server;  
NX_IP                               nat_ip;      
NX_IP                               local_ip;
NX_IP                               external_ip;
NX_PACKET_POOL                      nat_packet_pool; 
UINT                                error_counter = 0;     
                                                               

/* Configure the NAT network parameters. */

/* Set NetX IP packet pool packet size. This should be less than the Maximum Transmit Unit (MTU) of
   the driver (allow enough room for the Ethernet header plus padding bytes for frame alignment).  */
#define NX_NAT_PACKET_SIZE                          1536


/* Set the size of the NAT IP packet pool.  */
#define NX_NAT_PACKET_POOL_SIZE                     (NX_NAT_PACKET_SIZE * 10)

/* Set NetX IP helper thread stack size. */   
#define NX_NAT_IP_THREAD_STACK_SIZE                 2048

/* Set the server IP thread priority */
#define NX_NAT_IP_THREAD_PRIORITY                   2

/* Set ARP cache size of a NAT ip instance. */
#define NX_NAT_ARP_CACHE_SIZE                       1024 

/* Set NAT entries memory size. */
#define NX_NAT_ENTRY_CACHE_SIZE                     1024

/* Define NAT IP addresses, local host private IP addresses and external host IP address. */
#define NX_NAT_LOCAL_IPADR              (IP_ADDRESS(192, 168, 2, 1))  
#define NX_NAT_LOCAL_HOST1              (IP_ADDRESS(192, 168, 2, 3))
#define NX_NAT_LOCAL_HOST2              (IP_ADDRESS(192, 168, 2, 10)) 
#define NX_NAT_LOCAL_GATEWAY            (IP_ADDRESS(192, 168, 2, 1))    
#define NX_NAT_LOCAL_NETMASK            (IP_ADDRESS(255, 255, 255, 0))
#define NX_NAT_EXTERNAL_IPADR           (IP_ADDRESS(192, 168, 0, 10))   
#define NX_NAT_EXTERNAL_HOST            (IP_ADDRESS(192, 168, 0, 100))   
#define NX_NAT_EXTERNAL_GATEWAY         (IP_ADDRESS(192, 168, 0, 1))    
#define NX_NAT_EXTERNAL_NETMASK         (IP_ADDRESS(255, 255, 255, 0))  

/* Create NAT structures for preloading NAT tables with static 
   entries for local server hosts. */
NX_NAT_TRANSLATION_ENTRY            server_inbound_entry_icmp;
                                                                          
/* Define thread prototypes.  */   
static void     ntest_0_entry(ULONG thread_input);
extern void    _nx_ram_network_driver(struct NX_IP_DRIVER_STRUCT *driver_req);    
                                                                        
/* Define main entry point.  */

int main()
{

    /* Enter the ThreadX kernel.  */
    tx_kernel_enter();
}


/* Define what the initial system looks like.  */

void    tx_application_define(void *first_unused_memory)
{

UINT     status;
UCHAR    *pointer;
    
    /* Initialize the NetX system. */
    nx_system_initialize();
    
    /* Setup the pointer to unallocated memory.  */
    pointer =  (UCHAR *) first_unused_memory;
                          
    /* Create the main thread.  */
    tx_thread_create(&ntest_0, "thread 0", ntest_0_entry, 0,  
                     pointer, DEMO_STACK_SIZE, 
                     4, 4, TX_NO_TIME_SLICE, TX_AUTO_START);
    pointer =  pointer + DEMO_STACK_SIZE;    

    /* Create NAT packet pool. */   
    status =  nx_packet_pool_create(&nat_packet_pool, "NAT Packet Pool", 
                                    NX_NAT_PACKET_SIZE, pointer, 
                                    NX_NAT_PACKET_POOL_SIZE);

    /* Update pointer to unallocated (free) memory. */
    pointer = pointer + NX_NAT_PACKET_POOL_SIZE;    

    /* Check status.  */
    if (status)
        return;
                            
    /* Create IP instances for NAT server (global network) */
    status = nx_ip_create(&nat_ip, "NAT IP Instance", NX_NAT_EXTERNAL_IPADR, NX_NAT_EXTERNAL_NETMASK, 
                          &nat_packet_pool, _nx_ram_network_driver, pointer, 
                          NX_NAT_IP_THREAD_STACK_SIZE, NX_NAT_IP_THREAD_PRIORITY);

    /* Update pointer to unallocated (free) memory. */
    pointer =  pointer + NX_NAT_IP_THREAD_STACK_SIZE;

    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }
                 
    /* Set the private interface(private network).  */
    status += nx_ip_interface_attach(&nat_ip, "Private Interface", NX_NAT_LOCAL_IPADR, NX_NAT_LOCAL_NETMASK, _nx_ram_network_driver);
             
    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }                
                                     
    /* Create IP instances for Local network IP instance */
    status = nx_ip_create(&local_ip, "Local IP Instance", NX_NAT_LOCAL_HOST1, NX_NAT_LOCAL_NETMASK, 
                          &nat_packet_pool, _nx_ram_network_driver, pointer, 
                          NX_NAT_IP_THREAD_STACK_SIZE, NX_NAT_IP_THREAD_PRIORITY);

    /* Update pointer to unallocated (free) memory. */
    pointer =  pointer + NX_NAT_IP_THREAD_STACK_SIZE;

    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }
                  
    /* Create IP instances for external network IP instance */
    status = nx_ip_create(&external_ip, "External IP Instance", NX_NAT_EXTERNAL_HOST, NX_NAT_EXTERNAL_NETMASK, 
                          &nat_packet_pool, _nx_ram_network_driver, pointer, 
                          NX_NAT_IP_THREAD_STACK_SIZE, NX_NAT_IP_THREAD_PRIORITY);

    /* Update pointer to unallocated (free) memory. */
    pointer =  pointer + NX_NAT_IP_THREAD_STACK_SIZE;

    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }

    /* Set the global network gateway for NAT IP instance.  */
    status = nx_ip_gateway_address_set(&nat_ip, NX_NAT_EXTERNAL_GATEWAY);
                       
    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }                     
    
    /* Set the global network gateway for Local IP instance.  */
    status = nx_ip_gateway_address_set(&local_ip, NX_NAT_LOCAL_GATEWAY);
                       
    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }                     
    
    /* Set the global network gateway for External IP instance.  */
    status = nx_ip_gateway_address_set(&external_ip, NX_NAT_EXTERNAL_GATEWAY);
                       
    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }                     

    
    /* Enable ARP and supply ARP cache memory for NAT IP isntance. */
    status =  nx_arp_enable(&nat_ip, (void **) pointer, 
                            NX_NAT_ARP_CACHE_SIZE);
                         
    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }           
    
    /* Update pointer to unallocated (free) memory. */
    pointer = pointer + NX_NAT_ARP_CACHE_SIZE;
                                              
    /* Enable ARP and supply ARP cache memory for Local IP isntance. */
    status =  nx_arp_enable(&local_ip, (void **) pointer, 
                            NX_NAT_ARP_CACHE_SIZE);
                         
    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }           
    
    /* Update pointer to unallocated (free) memory. */
    pointer = pointer + NX_NAT_ARP_CACHE_SIZE;
                                             
    /* Enable ARP and supply ARP cache memory for External IP isntance. */
    status =  nx_arp_enable(&external_ip, (void **) pointer, 
                            NX_NAT_ARP_CACHE_SIZE);
                         
    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }           
    
    /* Update pointer to unallocated (free) memory. */
    pointer = pointer + NX_NAT_ARP_CACHE_SIZE;

    /* Enable ICMP. */
    nx_icmp_enable(&nat_ip);   
    nx_icmp_enable(&local_ip);   
    nx_icmp_enable(&external_ip);    
                                    
    /* Create a NetX NAT server and cache with a global interface index.  */
    status =  nx_nat_create(&nat_server, &nat_ip, 0, pointer, NX_NAT_ENTRY_CACHE_SIZE);
                             
    /* Check status.  */
    if (status)
    {
        error_counter++;
        return;
    }           

    /* Update pointer to unallocated (free) memory. */
    pointer = pointer + NX_NAT_ENTRY_CACHE_SIZE;                
}                    

/* Define the test threads.  */

static void    ntest_0_entry(ULONG thread_input)
{

UINT        status;
NX_PACKET   *my_packet;

    NX_PARAMETER_NOT_USED(thread_input);

    /***********************************/
    /*       Disable NAT feature       */    
    /***********************************/   
    /* Local Host ping External Host address.  */
    status =  nx_icmp_ping(&local_ip, NX_NAT_EXTERNAL_HOST, DEMO_DATA, sizeof(DEMO_DATA), &my_packet, NX_IP_PERIODIC_RATE);
                
    /* Check status.  */
    if (status == NX_SUCCESS)
    {                             
        error_counter++;
        return;
    }                            

    /* Check the NAT forwarded count.  */
#ifndef NX_DISABLE_NAT_INFO
    if ((nat_server.forwarded_packets_received != 0) || (nat_server.forwarded_packets_sent != 0) ||(nat_server.forwarded_packets_dropped != 0)) 
    {                             
        error_counter++;
        return;
    }
#endif
         
    /* External Host ping NAT External address, NAT IP instance will response the requet.  */
    status = nx_icmp_ping(&external_ip, NX_NAT_EXTERNAL_IPADR, DEMO_DATA, sizeof(DEMO_DATA), &my_packet, NX_IP_PERIODIC_RATE);
               
    /* Check status.  */    
    if ((status != NX_SUCCESS) || (my_packet == NX_NULL) || (my_packet -> nx_packet_length != 28))
    {                             
        error_counter++;
        return;      
    }

    /* Check the NAT forwarded count.  */
#ifndef NX_DISABLE_NAT_INFO
    if ((nat_server.forwarded_packets_received != 0) || (nat_server.forwarded_packets_sent != 0) ||(nat_server.forwarded_packets_dropped != 0)) 
    {                            
        error_counter++;
        return;
    }
#endif
              
    /***********************************/
    /*       Enable NAT feature        */    
    /***********************************/  

    /* Enable the NAT service.  */
    nx_nat_enable(&nat_server);          

    /* Local Host ping External Host address.  */
    status =  nx_icmp_ping(&local_ip, NX_NAT_EXTERNAL_HOST, DEMO_DATA, sizeof(DEMO_DATA), &my_packet, NX_IP_PERIODIC_RATE);
   
    if ((status != NX_SUCCESS) || (my_packet == NX_NULL) || (my_packet -> nx_packet_length != 28))
    {                            
        error_counter++;
        return;
    }           

    /* Check the NAT forwarded count.  */
#ifndef NX_DISABLE_NAT_INFO
    if ((nat_server.forwarded_packets_received != 2) || (nat_server.forwarded_packets_sent != 2) ||(nat_server.forwarded_packets_dropped != 0)) 
    {                            
        error_counter++;
        return;
    }
#endif          

    /* External Host ping NAT External address, NAT IP instance will response the requet.  */
    status =  nx_icmp_ping(&external_ip, NX_NAT_EXTERNAL_IPADR, DEMO_DATA, sizeof(DEMO_DATA), &my_packet, NX_IP_PERIODIC_RATE);
   
    if ((status != NX_SUCCESS) || (my_packet == NX_NULL) || (my_packet -> nx_packet_length != 28))
    {                            
        error_counter++;
        return;
    }   
                
    /* Check the NAT forwarded count.  NAT receive the ping request, but can not forward this packet to local network.  discard it.  */
#ifndef NX_DISABLE_NAT_INFO
    if ((nat_server.forwarded_packets_received != 3) || (nat_server.forwarded_packets_sent != 2) ||(nat_server.forwarded_packets_dropped != 1)) 
    {                              
        error_counter++;
        return;
    }
#endif 

    /**********************************************/
    /*       Preload a inbound entry for ICMP     */    
    /**********************************************/  

    /* Calling NAT API to create a inbound entry.  */
    status = nx_nat_inbound_entry_create(&nat_server, &server_inbound_entry_icmp, NX_NAT_LOCAL_HOST1, 0, 0, NX_PROTOCOL_ICMP);    

    if (status != NX_SUCCESS)
    {                             
        error_counter++;
        return;
    }            

    /* External Host ping NAT External address, LOCAL HOST1 will response all inbound icmp request from external network.  */
    status =  nx_icmp_ping(&external_ip, NX_NAT_EXTERNAL_IPADR, DEMO_DATA, sizeof(DEMO_DATA), &my_packet, NX_IP_PERIODIC_RATE);
   
    if ((status != NX_SUCCESS) || (my_packet == NX_NULL) || (my_packet -> nx_packet_length != 28))
    {                             
        error_counter++;
        return;
    }  

    /* Check the NAT forwarded count.  */
#ifndef NX_DISABLE_NAT_INFO
    if ((nat_server.forwarded_packets_received != 5) || (nat_server.forwarded_packets_sent != 4) ||(nat_server.forwarded_packets_dropped != 1)) 
    {                            
        error_counter++;
        return;
    }
#endif  
}
#endif