nat_cleanup.c

vxworks下ppp的实现源码

/* nat_cleanup.c - library that supplies nat_cleanup() */

/* Copyright 2000-2003 Wind River Systems, Inc. */

/* @format.tab-size 4, @format.use-tabs true, @format.new-line lf */

/*
modification history
--------------------
01f,29aug03,zhu  updated the format for refgen
01e,16jun03,myz  Use new fragment translation cleanup routine.
01d,12may03,myz  added natIcmpErrorHookRemove in nat_cleanup.
01c,25apr03,myz  make dllFreeList a global func and add delays in nat_cleanup
01b,24apr03,zhu  updated copyright
01a,21apr03,myz enhanced nat_cleanup function, and added dllFreeList  
040803  vks     updated Copyright info
040303  vks     replaced table_free with free
092502  vvv     modified fragment lists to use lstLib instead of rw_container
092402  vvv     replaced rw_container references with direct linked list
		access to improve performance
030901	tk	Add call to delete natInitSync semaphore
*/

/*
DESCRIPTION

This library provides nat_cleanup(), a routine that you can use to 
shut down WIND NET NAT entirely, thus freeing all its associated 
resources (configuration information, tasks, message queues, etc.).

*/

#include "nat.h"

void ipFilterHookDelete(void); /* Missing from VxWorks headers */
extern void natIcmpErrorHookRemove (void);

/****************************************************************************/
static void nat_free_udp_translation_list (void);
static void nat_free_icmp_translation_list (void);

/****************************************************************************/


/****************************************************************************
*
* nat_cleanup - shut down WIND NET NAT, free all associated resources
*
* Call this function to shut down WIND NET NAT entirely and free all its 
* associated resources.  
* 
* 'Note:' To merely pause WIND NET NAT, you can call natEnable() with 
* the <enable> parameter set to FALSE. 
*
*/

void nat_cleanup (void)
{
	IP_TRANSLATION_ENTRY *sptr_ip_translation_entry;

	/* Remove the VxWorks IP Filter Hook */
	ipFilterHookDelete();

	/* remove the NAT ICMP error hook */

	natIcmpErrorHookRemove();

	/* give the unhooked NAT engine some time in case it's in progress */

	taskDelay(2);

	/* delete the NAT task */

	natTaskDelete();

	/* cleanup the rest of resource */

	for (sptr_ip_translation_entry = (IP_TRANSLATION_ENTRY *) DLL_FIRST ((DL_LIST *) &nat.natg.ip_translation_list);
		sptr_ip_translation_entry != NULL;
		sptr_ip_translation_entry = (IP_TRANSLATION_ENTRY *) DLL_FIRST ((DL_LIST *) &nat.natg.ip_translation_list))
		{
		dllRemove ((DL_LIST *) &nat.natg.ip_translation_list, (DL_NODE *) sptr_ip_translation_entry);

		if (sptr_ip_translation_entry->sptr_local_address_use_entry != NULL)
			{
			sptr_ip_translation_entry->sptr_local_address_use_entry->address_in_use = FALSE;
			}

		free (sptr_ip_translation_entry);
		}	

	natFragTranCleanup(nat.pFragTranResrc);
		
	delete_tcp_connection_entry_list (&nat.nats.tcp_translation_list);

	nat_free_udp_translation_list ();

	nat_free_icmp_translation_list ();
		
	/* Clean-up passthrough list */
        lstFree (&nat.passthru_list);

	/* Clean-up agent list */
        lstFree (&nat.agent_list);

	/* Clean-up bind list */
	lstFree (&nat.bind_list);

    /* Clean up the semaphores */
    if (udpListLock)
        semDelete (udpListLock);

    if (tcpListLock)
        semDelete (tcpListLock);

    if (spoofingPortLock)
        semDelete (spoofingPortLock);

    if (natInitSync)
        semDelete (natInitSync);

    if (ipListLock)
	    semDelete(ipListLock);

    if (bindListLock)
	    semDelete(bindListLock);

    if (agentListLock)
	    semDelete(agentListLock);

    if (nat.natg.global_address_pool != NULL) 
	{
	free (nat.natg.global_address_pool);

	nat.natg.global_address_pool = NULL;
	}

    nat.enabled = FALSE;
    }
/************************************************************************/
void delete_sequence_entry_list (SEQUENCE_HEADER *sptr_sequence_list)
{
	dllFreeList ((DL_LIST *) sptr_sequence_list);
}	

/***************************************************************************
*
* dllFreeList - Free a link list
*
* Free a link list.
* 
* NOMANUAL
*/

void dllFreeList 
    (
    DL_LIST * pList
    )
    {
    DL_NODE * pNode;
    DL_NODE * pPrevNode;

    pNode = DLL_FIRST(pList);

    while (pNode)
        {
        pPrevNode = pNode;
        pNode = DLL_NEXT(pNode);
        free((void *)pPrevNode);
        }

    dllInit(pList);
    }

/************************************************************************/
void delete_tcp_connection_entry_list (TCP_TRANSLATION_HEADER *sptr_tcp_translation_list)
{
	TCP_TRANSLATION_ENTRY *sptr_tcp_translation_entry;

	for (sptr_tcp_translation_entry = (TCP_TRANSLATION_ENTRY *) dllGet ((DL_LIST *) sptr_tcp_translation_list);
		sptr_tcp_translation_entry != NULL;
		sptr_tcp_translation_entry = (TCP_TRANSLATION_ENTRY *) dllGet ((DL_LIST *) sptr_tcp_translation_list))
		{
		delete_sequence_entry_list (&sptr_tcp_translation_entry->local_sequence_delta_list);
		delete_sequence_entry_list (&sptr_tcp_translation_entry->global_sequence_delta_list);

		free (sptr_tcp_translation_entry);
		}
}	
/************************************************************************/
static void nat_free_udp_translation_list (void)
{
	UDP_TRANSLATION_ENTRY* p_udp_entry;
	UDP_TRANSLATION_ENTRY* p_next_udp_entry;
	
	for (p_udp_entry = nat.nats.udp_translation_list.sptr_forward_link; p_udp_entry != NULL; p_udp_entry = p_next_udp_entry)
		{
		p_next_udp_entry = p_udp_entry->link.sptr_forward_link;
		
		dllRemove ((DL_LIST*) &nat.nats.udp_translation_list, (DL_NODE*) p_udp_entry);
		
		free (p_udp_entry);
		}
}	
/************************************************************************/
static void nat_free_icmp_translation_list (void)
{
	ICMP_TRANSLATION_ENTRY* p_icmp_entry;
	ICMP_TRANSLATION_ENTRY* p_next_icmp_entry;
	
	for (p_icmp_entry = nat.nats.icmp_translation_list.sptr_forward_link; p_icmp_entry != NULL; p_icmp_entry = p_next_icmp_entry)
		{
		p_next_icmp_entry = p_icmp_entry->link.sptr_forward_link;
		
		dllRemove ((DL_LIST*) &nat.nats.icmp_translation_list, (DL_NODE*) p_icmp_entry);
		
		free (p_icmp_entry);
		}
}