igmp.c

用于嵌入式系统的TCP/IP协议栈及若干服务

/*
*            Copyright (c) 1998-2001 by NETsilicon Inc.
*
*  This software is copyrighted by and is the sole property of
*  NETsilicon.  All rights, title, ownership, or other interests
*  in the software remain the property of NETsilicon.  This
*  software may only be used in accordance with the corresponding
*  license agreement.  Any unauthorized use, duplication, transmission,
*  distribution, or disclosure of this software is expressly forbidden.
*
*  This Copyright notice may not be removed or modified without prior
*  written consent of NETsilicon.
*
*  NETsilicon, reserves the right to modify this software
*  without notice.
*
*  NETsilicon
*  411 Waverley Oaks Road                  USA 781.647.1234
*  Suite 227                               http://www.netsilicon.com
*  Waltham, MA 02452                       [e-mail]
*
*************************************************************************
*  $Name: Fusion 6.52 Fusion 6.51 $
*  $Date: 2001/11/28 17:57:03 $
*  $Source: M:/psisrc/stack/mcast/rcs/igmp.c $
*  $Revision: 1.24 $
**************************************************************************
*                         - Revision Log -                              *
* Who   When        Why
*
* FND   09/28/01    Rename t_start/t_delete to fns_t_start/fns_t_delete
*                   to fix conflict with pSOS.
*
**************************************************************************
*  File Description: IGMP V2
**************************************************************************/
#include "std.h"
#ifdef IGMP_PROTOCOL
#include "flags.h"
#include "fr.h"
#include "netdev.h"
#include "netioc.h"
#include "fns_mem.h"
#include "fnsproto.h"
#include "igmp.h"
#include "enet.h"
#include "nerrno.h"
#include "debug.h"
#include "fns_heap.h"

#define t_start fns_t_start
#define t_delete fns_t_delete

/** external functions **/
import  netdev  *ll_dev_2_ndp (char * devname);

export igmp_entry   *igmp_tbl;
export u32      igmp_entries;

/** internal functions **/
u32 igmp_num (int i, u8 max_response_time );
int igmp_do_send ( IGMP_T *packet, netdev *ndp, u32 ipdest );
int igmp_send_report( igmp_entry *igmp_tab_entry );
export int igmp_send_general_query (char *devname, u8 max_response_time );
export int igmp_send_group_query ( igmp_entry *entry, u8 max_response_time );
int igmp_update (void *uarg);
int igmp_start_t (netdev *ndp, a32 *ipaddr, u8 max_response_time );


static u32 modulus =    9997;
static u32 offset;

/*********************************************************************
 *
 * igmp_is_v2(void)
 *
 * DESCRIPTION:  For any external code which wants to know if we are
 *               configured for IGMP V2 operation via the IGMP_VERSION_2
 *               switch but doesn't want to include igmp.h
 *
 * RETURNS:      1 if we are v2, 0 if not
 *
 **/
int igmp_is_v2(void)
{
#ifdef IGMP_VERSION_2
    return 1;
#else
    return 0;
#endif
}

/*********************************************************************
 ** ip_add_multi_route()
 *
 *  PARAMETERS: 1. IP multicast address.
 *              2. Device name as in ncdev.c.
 *              3. local_mc is a boolean set to 1 if we don't
 *                 want this address to participate in IGMP
 *
 *  DESCRIPTION:    1. Check if it is proper Multicast IP address.
 *                  2. Adds Multi. IP address to the routing table on
 *                     the selected device.
 *                  3. Allocates the entry in the igmp_tbl.
 *                  4. Sets the state of new entry to DELAY so it is
 *                     sent at least twice.
 *                  5. Sends igmp report of the new entry.
 *
 *  RETURNS: 0   - OK
 *           > 1 - error
**********************************************************************/
int ip_add_multi_route (char *devname, char *ip_address, int is_localmc )
{
    netdev      *ndp;
    int         err;
    int         i = 0;
    u32         ip_address_u32;
    use_critical;

    err = 0;

    ip_address_u32 = MemToHost32((u8 *)ip_address);
    if ( !(is_D_class((u8 *)ip_address)) )
        return FNS_EDESTADDRREQ;

    if ((ndp = ll_dev_2_ndp(devname)) == (netdev *)0)
        return FNS_ENODEV;

    /* Is this interface already a member of the specified multicast group?
	   If so, all we need to do here is to increment the reference count for
	   the interface. */
    if ( (i = igmp_find (ip_address_u32, ndp)) >= 0 ) {
		/* This interface already a member of this multicast group */
        igmp_tbl[i].refs++;
        return 0;
	} /* if */
	
	/* If we get down here, then this is the first membership of the specified
	   interface in the specified multicast group. So we need to create a new
	   membership entry, provided we have room for it in our membership table */
    if (igmp_entries >= IGMP_CNT) {
#ifdef DEBUG
        os_printf("ip_add_multi_route: IGMP reference table full\n");
#endif
        return FNS_ETOOMANYREFS;
    }

    /* If this is an ethernet interface, invoke the processing to take advantage
	   of ethernet hardware's ethernet layer multicasting capability */
	ndp->nd_xflags |= F_X_MULTI_ADDR;
    if (IS_LAN_TYPE((int)ndp->nd_lladdr.a_type)) {
        err = arp_multi_add (ndp, ip_address);
        if (err) {
			return(err);
		}
	}

	/* The IGMP_ALLHOSTS group doesn't need an entry */
    if ( ip_address_u32 == IGMP_ALLHOST ) {
		return(0);
	}

    /* Well, all the condtions are met, we are going to add an entry to the 
	   IGMP table. */

    /* go critical while manipulating the IGMP membership table */
    critical;
    /* Look for a free entry in the IGMP table to use for this new membership */
    for (i = 0; i < IGMP_CNT; i++) {
        if (igmp_tbl[i].state == IGMP_FREE) {
            break;
		} /* if */
	} /* for */

    if (i >= IGMP_CNT) {
		/* Something is seriously wrong -- earlier we decided that our IGMP table
		   isn't full, yet we just looked for a free entry and didn't find one. */
        normal;
#ifdef DEBUG
        os_printf("ip_add_multi_route: IGMP reference table full (inconsistent)\n");
#endif
        return FNS_ETOOMANYREFS;
    }

    igmp_entries++;
    igmp_tbl[i].state = IGMP_IDLE;
    igmp_tbl[i].ndp = ndp;
    igmp_tbl[i].ip_multi = ip_address_u32;
    igmp_tbl[i].seed = (int)ip_address_u32;
    igmp_tbl[i].refs = 1;

    if ( is_localmc ) {
        /* OL:  Local Multicast does not need timers*/
        igmp_tbl[i].timer = (tcb *)0;
    } else {
        if ( (igmp_tbl[i].timer = t_new((tcb *)0
            , igmp_update, &igmp_tbl[i],
            igmp_num(i, 100), F_T_STOPPED))
              == (tcb *)0) {
            normal;
#ifdef DEBUG
            os_printf("ip_add_multi_route: out of heap for timer creation !!!!!\n");
#endif
            return FNS_ENOMEM;
        }
    }
    /* Finished manipulating the membership table */
    normal;


    /* JPP locals do not participate in reports */
    if( !is_localmc ) {
        igmp_send_report( &igmp_tbl[i] );
        igmp_tbl[i].state = IGMP_DELAY;
        igmp_tbl[i].last_2_report = true;
        t_start (igmp_tbl[i].timer, igmp_num(i, 100));
    } else
        igmp_tbl[i].state = IGMP_STATIC;

    return err;
}

/*********************************************************************
 ** igmp_send_leave( igmpentry *entry )
 *
 *  PARAMETERS:     entry - entry in igmp table.
 *
 *  DESCRIPTION:    Send a v2 leave message if conditions are OK.
 *
 *  RETURNS:    0 - OK
 *              1 - error
***********************************************************************/
void igmp_send_leave( igmp_entry *entry )
{
#ifdef IGMP_VERSION_2
    netdev *ndp = entry->ndp;
    IGMP_T packet[SIZEOF_IGMP_T];

    /* Only can send if:
            1.  Built for V2

            2.  We have are sending IGMPv2 reports (we haven't heard
                an IGMPv1 Query in IGMP_V1_ROUTER_PRESENT_TIMEOUT seconds).

            3.  We were the last host to send a membership report for
                this group.
    */

    if( ndp->v1_router_present || !entry->last_2_report ) {
        return;
    }

    /* Fill in the packet fields */
    packet[IGMP_T_IGMP_TYPE] = IGMP_V2_LEAVE;
    /* unused field for reports */
    packet[IGMP_T_MAX_RESP_TIME] = 0;
    HostToMem32(&packet[IGMP_T_IP_ADDR], entry->ip_multi);
    igmp_do_send ( packet, entry->ndp, IGMP_ALLROUTER );
#else
    return;
#endif
}



/*********************************************************************
 ** ip_del_multi_route()
 *
 *  PARAMETERS:     1. Device name as in ncdev.c
 *          2. IP multicast address.
 *
 *  DESCRIPTION:    1. Check if it is proper Multicast IP address.
 *                  2. Deletes Multi. IP address from the routing table of
 *                  the selected device.
 *                  3. Changes the sate of the igmp_tbl entry.
 *                  4. Deletes the allocated time queue.
 *
 *  RETURNS:    0 - OK
 *              1 - error
***********************************************************************/
int ip_del_multi_route (char * devname, char *ip_address)
{
    netdev      *ndp;
    int         err;
    int         i = 0;
    u32         ip_address_u32;

    use_critical;

    err = 0;
    if ( !(is_D_class((u8 *)ip_address)) )
    {
#ifdef DEBUG
        os_printf("ip_del_multi_route: wrong address\n");
#endif
        return FNS_EADDRNOTAVAIL;
    }
    if ((ndp = ll_dev_2_ndp(devname)) == (netdev *)0)
        return FNS_ENODEV;

    ip_address_u32 = MemToHost32((u8 *)ip_address);
    if ((i = igmp_find (ip_address_u32, ndp)) >= 0)
    {
        /* refs is the number of references to the address on this interface.
           If it is non-zero there is nothing more to be done.  If zero see
           below - we must remove it from the interface.
        */
        if (--igmp_tbl[i].refs) {
            return 0;
        }
    }
    else
    {
#ifdef DEBUG
        os_printf("ip_del_multi_route: address not in igmp table\n");
#endif
        return FNS_EADDRNOTAVAIL;
    }
    /* For IGMPv2 send a leave message */

    igmp_send_leave( &igmp_tbl[i] );
    critical;
    igmp_tbl[i].state = IGMP_FREE;
    igmp_tbl[i].last_2_report = false;
    igmp_entries--;
    /* OL: local multicast does not have a timer */
    if (igmp_tbl[i].timer != (tcb *)0)
        t_delete (igmp_tbl[i].timer);
    normal;
    /* OL: deleted interface to old router */
    /* OL: replaced comparison to AF_ETHER with macro  */
    if (IS_LAN_TYPE((int)ndp->nd_lladdr.a_type))
        err = arp_multi_del (ndp, ip_address);
    return err;

}

/*
 * dummy timer callback
 *
 */
int igmpdummy( void *dummy )
{
    return 0;
}

/*********************************************************************
 ** igmpinit ()
 *
 *  PARAMETERS:     prp - protocol structure
 *
 *  DESCRIPTION:    1. Allocates IGMP_CNT entries in the igm_tbl and
 *                  initialize them to 0.
 *
 *  RETURNS:    0 - OK
 *              1 - error
 *
***********************************************************************/
export int igmpinit (pr_t * prp)
{
    igmp_entry  *entry;