ospf_interface_events.c

vxworks下ospf协议栈

/* ospf_interface_events.c - used for executing interface events */

/* Copyright 1998 - 2003 Wind River Systems, Inc. */
#include "copyright_wrs.h"

/*
modification history
--------------------
02e,30jun03,agi Fixed SPR#88879, ospf does not clean up external LSDB when an 
                interface is brought down
02d,26may03,agi Changed rwos_get_system_elapsed_time_second() to
                ospf_get_system_elapsed_time_second()
02c,22apr03,ram	SPR#76812 Modifications for OSPF performance enhancements
02b,29jan03,asr Fix for SPR# 85573. Build, install & flood new router LSA after
                link down.
02a,03dec02,ram SPR#84312 - Change elapsed time to return seconds
23,29april02,ark Added in fix for SPR 75785
22,10April02,bt			modified to not generate Network-LSA for PTMP and POINT-to-POINT
21,22march02,kc            Fixed SPR74261. When triggering the interface down event to
                            reset the interface variables, it is necessary to flush all
                            lsas associated with the area if there is no more active
                            interface in that area.
 20,13october01,kc			Dynamic configuration changes.
19,06october01,kc  		Modified ospf_process_interface_backup_seen_event() and
                 			ospf_process_interface_wait_timer_event to calculate DR and BDR
                 			only if interface type is broadcast or NBMA.
18,3may01,jkw 				change ospf_reset_interface_variables_and_timers_and_destroy_all_associated_neighbor_connections
17,21may01,jkw 			add in new function for point to point
16,26september00,reshma	Added WindRiver CopyRight
15,25september00,reshma	RFC-1587 implementation for OSPF NSSA Option, also tested against ANVL.
14,07july00,reshma			Unix compatibility related changes.
13,04april00,reshma		Added some MIB support (Read only).Passed all important ANVL OSPF tests.
12,23december99,reshma		Compatibility with VxWorks-IP and VxWorks RTM-interface
11,28december98,jack		Compiled and added some comments
10,11november98,jack		Config changes, linted and big endian changes
09,30october98,jack		Incorporate changes for compilation on Vxworks
08,23august98,jack			ANVL tested OSPF with PATRICIA tree route table and no recursion
07,10august98,jack			PATRICIA Route Table Based OSPF Code Base
06,04june98,jack			Integration with RTM and BGP
05,24april98,jack			RTM changes
04,10july97,cindy			Pre-release v1.52b
03,02october97,cindy		Release Version 1.52
02,22october96,cindy		Release Version 1.50
01,05june96,cindy			First Beta Release
*/

/*
DESCRIPTION
ospf_interface_events.c is used for processing interface events.  Interface events include:
OSPF_INTERFACE_UP, OSPF_WAIT_TIMER, OSPF_BACKUP_SEEN, OSPF_NEIGHBOR_CHANGE, OSPF_LOOP_INDICATION,
OSPF_UNLOOP_INDICATION, OSPF_INTERFACE_DOWN.
This file is used whenever an interface event occurs.

*/




#include "ospf.h"
#if defined (__OSPF_VIRTUAL_STACK__)
#include "ospf_vs_lib.h"
#endif /* __OSPF_VIRTUAL_STACK__ */

/***********************************************************************************************************************************/
static char *ospf_interface_types[] =
{
	"",
	"Point To Point",
	"Broadcast",
	"OSPF_NBMA",
	"Point To Multipoint",
	"Virtual"
};

static char *ospf_interface_states[] =
{
    "Down",
    "Loopback",
    "Waiting",
    "Point To Point",
    "DR Other",
    "BackupDR",
    "DR "
};

static char *ospf_interface_events[] =
{
    "Interface Up",
    "Wait Timer",
    "Backup Seen",
    "Neighbor Change",
    "Loop Indication",
    "Unloop Indication",
    "Interface Down"
};

/***********************************************************************************************************************************/
static void ospf_calculate_backup_designated_router_and_designated_router_for_attached_network (OSPF_INTERFACE *sptr_interface,
	enum OSPF_INTERFACE_EVENT event);
static void ospf_interface_state_transition_printf (OSPF_INTERFACE *sptr_interface,enum OSPF_INTERFACE_EVENT event,
	enum OSPF_INTERFACE_STATE old_state);
static void ospf_calculate_point_to_point_network (OSPF_INTERFACE *sptr_interface);

/*************************************************************************
*
* ospf_process_interface_up_event - execute when interface comes up
*
* This routine will initialize the interface variables and bring up
* the interface specified.
*
* <sptr_interface> OSPF interface
*
* RETURNS: N/A
*
* ERRNO: N/A
*
* NOMANUAL
*/
/*****************************************************************************************//* section 9.3, State: Down (p. 66-67) */
void ospf_process_interface_up_event (OSPF_INTERFACE *sptr_interface)
{
	enum OSPF_INTERFACE_STATE old_state;
    OSPF_NEIGHBOR *sptr_neighbor = NULL;
	OSPF_NEIGHBOR *sptr_next_neighbor = NULL;

	OSPF_PRINTF_PROLOGUE (OSPF_PROLOGUE_PRINTF, "OSPF: Entering ospf_process_interface_up_event\r\n");

	old_state = sptr_interface->state;

	/* SPR 84312 -- Begin */
	sptr_interface->potential_neighbor.last_hello = ospf_get_system_elapsed_time_second ();
	/* SPR 84312 -- End */

	sptr_interface->potential_neighbor.periodic_inactivity_time_counter = 0x00000000L;
	sptr_interface->potential_neighbor.inactivity_timer_enabled = TRUE;

	ospf_send_hello (sptr_interface, NULL, FALSE);						/* begin periodic sending of Hello packets out the interface */

	if ((sptr_interface->type == OSPF_POINT_TO_POINT) || (sptr_interface->type == OSPF_POINT_TO_MULTIPOINT) || (sptr_interface->type == OSPF_VIRTUAL_LINK))
		{
		sptr_interface->state = OSPF_INTERFACE_POINT_TO_POINT;
        sptr_interface->point_timer_enabled = TRUE;
		}
	else if (sptr_interface->priority == 0x0000)
		{
		sptr_interface->state = OSPF_INTERFACE_DESIGNATED_ROUTER_OTHER;
		}
	else
		{
		sptr_interface->state = OSPF_INTERFACE_WAITING;
		sptr_interface->periodic_wait_time_counter = 0x00000000L;
		sptr_interface->wait_timer_enabled = TRUE;

		if (sptr_interface->type == OSPF_NBMA)
			{
			for (sptr_neighbor = sptr_interface->sptr_neighbor; sptr_neighbor != NULL;	sptr_neighbor = sptr_next_neighbor)
				{
				sptr_next_neighbor = sptr_neighbor->sptr_forward_link;
				if (sptr_neighbor->priority > 0x0000)				/* check if neighbor is eligible to become designated router */
					{
					ospf_execute_neighbor_state_machine (OSPF_START, sptr_neighbor->state, sptr_interface, sptr_neighbor);
					}
				}
			}
		}

	if (sptr_interface->type == OSPF_VIRTUAL_LINK)
		{
		sptr_interface->sptr_transit_area->flags._bit.virtual_up = TRUE;

		++ospf.number_of_virtual_links_in_Up_state;

		if (ospf.sptr_backbone_area != NULL)
			{
			if (ospf.sptr_backbone_area->lock_time == 0x00000000L)
				{
				/* SPR 84312 -- Begin */
				ospf.sptr_backbone_area->lock_time = ospf_get_system_elapsed_time_second ();
				/* SPR 84312 -- End */
				}
			}
		}
	else
		{
		sptr_interface->sptr_area->build_router = TRUE;		/* section 12.4, item (2) (page 115) */
		}

	++sptr_interface->sptr_area->number_of_interfaces_in_up_state;

	ospf_interface_state_transition_printf (sptr_interface, OSPF_INTERFACE_UP, old_state);

	++sptr_interface->events;

	/* SPR 84312 -- Begin */
	sptr_interface->up_time = ospf_get_system_elapsed_time_second ();
	/* SPR 84312 -- End */

	return;
}

/*************************************************************************
*
* ospf_process_interface_wait_timer_event - execute when interface wait timer event is received
*
* This routine will either calculate the point to point network if the
* interface type is point to point or execute the DR and BDR election
* process.
*
* <sptr_interface> OSPF interface
*
* RETURNS: N/A
*
* ERRNO: N/A
*
* NOMANUAL
*/
/*****************************************************************************************//* section 9.3, State: Waiting (p. 67) */
void ospf_process_interface_wait_timer_event (OSPF_INTERFACE *sptr_interface)
{
	OSPF_PRINTF_PROLOGUE (OSPF_PROLOGUE_PRINTF, "OSPF: Entering ospf_process_interface_wait_timer_event\r\n");

	sptr_interface->wait_timer_enabled = FALSE;

    if (sptr_interface->state == OSPF_INTERFACE_POINT_TO_POINT)
		{
		ospf_calculate_point_to_point_network (sptr_interface);
		}
	else
		{
        ospf_calculate_backup_designated_router_and_designated_router_for_attached_network (sptr_interface, OSPF_WAIT_TIMER);
        }

	return;
}

/*************************************************************************
*
* ospf_process_interface_backup_seen_event - execute when interface backup seen event is received
*
* This routine will execute the DR and BDR election process.
*
* <sptr_interface> OSPF interface
*
* RETURNS: N/A
*
* ERRNO: N/A
*
* NOMANUAL
*/
/*****************************************************************************************//* section 9.3, State: Waiting (p. 67) */
void ospf_process_interface_backup_seen_event (OSPF_INTERFACE *sptr_interface)
{
	OSPF_PRINTF_PROLOGUE (OSPF_PROLOGUE_PRINTF, "OSPF: Entering ospf_process_interface_backup_seen_event\r\n");

	sptr_interface->wait_timer_enabled = FALSE;
	ospf_calculate_backup_designated_router_and_designated_router_for_attached_network (sptr_interface, OSPF_BACKUP_SEEN);

	return;
}

/*************************************************************************
*
* ospf_process_interface_neighbor_change_event - execute when interface neighbor change event is received
*
* This routine will execute the DR and BDR election process if
* the interface type is either broadcast or nbma.
*
* <sptr_interface> OSPF interface
*
* RETURNS: N/A
*
* ERRNO: N/A
*
* NOMANUAL
*/
/*************************************************************************//* section 9.3, State: DR Other, Backup, or DR (p. 68) */
void ospf_process_interface_neighbor_change_event (OSPF_INTERFACE *sptr_interface)
{
	OSPF_PRINTF_PROLOGUE (OSPF_PROLOGUE_PRINTF, "OSPF: Entering ospf_process_interface_neighbor_change_event\r\n");

	sptr_interface->flags._bit.neighbor_change = FALSE;

	sptr_interface->wait_timer_enabled = FALSE;

	if ((sptr_interface->type == OSPF_BROADCAST) || (sptr_interface->type == OSPF_NBMA))
		{
		ospf_calculate_backup_designated_router_and_designated_router_for_attached_network (sptr_interface, OSPF_NEIGHBOR_CHANGE);
		}

	return;
}

/*************************************************************************
*
* ospf_process_interface_loop_indication_event - execute when interface loop indication event is received
*
* This routine will reset all the interface variables and timers.  This
* routine will destroy all the associated neighbor connections with
* the interface specified.
*
* <sptr_interface> OSPF interface
*
* RETURNS: N/A
*
* ERRNO: N/A
*
* NOMANUAL
*/
/*********************************************************************************************//* section 9.3, State: Any (p. 68) */
void ospf_process_interface_loop_indication_event (OSPF_INTERFACE *sptr_interface)
{
	OSPF_PRINTF_PROLOGUE (OSPF_PROLOGUE_PRINTF, "OSPF: Entering ospf_process_interface_loop_indication_event\r\n");

	ospf_reset_interface_variables_and_timers_and_destroy_all_associated_neighbor_connections (sptr_interface, OSPF_LOOP_INDICATION, OSPF_INTERFACE_LOOPBACK);