ospf_mib_stub.c

vxworks下ospf协议栈

     * be allocated by the caller. Loop through the varbinds and determine if
     * there is an object whose type is octet string.
     */
    rc = OK;
    for (group_vbp = vbp; group_vbp != NULL; group_vbp = group_vbp->vb_link )
    {
        if ( (group_vbp->vb_ml.ml_leaf->expected_tag == VT_STRING) ||
             (group_vbp->vb_ml.ml_leaf->expected_tag == VT_OPAQUE) )
        {
            /* for ospfLsdbTable, ospfLsdbAdvertisement is the only object using octet
             * string.
             */
            if ( group_vbp->vb_ml.ml_last_match != LEAF_ospfLsdbAdvertisement )
                continue;

            /* copy instance portion into a buffer. This buffer will be used to return
             * the next instance by the MIB API. This is necessary because the main 
             * purpose for this transaction here is to query MIB API for the size of 
             * the ospfLsdbAdvertisement object so that we can allocate a buffer
             * (with the exact size) that will be used by MIB API to return the value 
             * of the advertisement. Therefore, we are not really interesting about 
             * the index value for the next instance.
             */
            memset( (char *)inst_oid, 0, sizeof(OIDC_T)*ospfLsdbEntry_INST_LEN );
            inst_len = tcount;
            if ( inst_len != 0 )
                copy_oids( inst_oid, tlist, inst_len );

            /* send a simple get request to query MIB API for the size of the
             * advertisement for this row
             */
            request.pInstance = (ulong_t *)inst_oid;
            request.instanceLen = (ushort_t)inst_len;
            request.numObjects = 1;
            memset( (char *)&object, 0, sizeof(mApiObject_t) );
            request.pObjectList = &object;
            request.pObjectList->oidPrefixEnum = group_vbp->vb_ml.ml_last_match +
                                                 ospfMapiLsdb_OID_OFFSET;
            request.pObjectList->pValueBuf = NULL;
            request.pObjectList->valueLen = 0;
            rc = ospfMapiGetLsdb( &request, reqType );
            if ( rc == ERROR )
            {
                ospf_envoy_processGetRespError( pktp, vbp, reqType, request.error );
                ospfEnvoyPrintf(("ospfEnvoy_getLsdb:failed\n"));
                return;
            }

            /* expect an exception to be set by MIB API */
            if ( request.pObjectList->exception != MAPI_BUFFER_TOO_SHORT )
            {
                ospfEnvoyPrintf(("ospfEnvoy_getLsdb:exception not buffer too short\n"));
                rc = ERROR;
                break;
            }

            /* MIB API should return the size of the lsdb */
            if ( request.pObjectList->valueLen == 0 )
            {
                ospfEnvoyPrintf(("ospfEnvoy_getLsdb:no buflen returned by MIB API\n"));
                rc = ERROR;
                break;
            }

            pEnvoyReq->octetBufLen = request.pObjectList->valueLen;
            pEnvoyReq->pOctetBuf = SNMP_memory_alloc( pEnvoyReq->octetBufLen );
            if ( pEnvoyReq->pOctetBuf == NULL )
            {
                ospfEnvoyPrintf(("ospfEnvoy_getLsdb:memory alloc(%ld) failed\n",
                                 pEnvoyReq->octetBufLen));
                rc = ERROR;
                break;
            }

            /* clear the request message structure */
            memset( (char *)&request, 0, sizeof(mApiRequest_t) );

            /* mark this buffer as dynamic */
            pEnvoyReq->dynamic = TRUE;
            break;  /* there can be only one octet string object in a row */
        }
    }

    if ( rc == ERROR )
    {
        ospf_envoy_setGenError( pktp, vbp, reqType );
        return;
    }

    /* build the MIB API request message */
    memset( (char *)&request, 0, sizeof(mApiRequest_t) );
    rc = ospf_envoy_buildGetReq( tcount, tlist, vbp, pEnvoyReq, &request,
                                 ospfMapiLsdb_OID_OFFSET );
    if ( rc == ERROR )
    {
        /* free the allocated memory only if we have just allocated it in this 
         * transaction (i.e. pEnvoyReq->dynamic is set). It is necessary to
         * determine if the buffer is allocated within the context of current 
         * transaction because the buffer pointed to by pEnvoyReq->pOctetBuf
         * may have been allocated during a previous transaction and that buffer
         * should only be freed by envoy snmp after the packet has been encoded 
         * (sometimes after getproc_got_string() is called). When the current
         * transaction takes place, it is possible that the buffer pointed to by 
         * pEnvoyReq->pOctetBuf may not be null (i.e. envoy snmp has yet freed 
         * it). Therefore, we must make sure that we only free the memory that is
         * allocated in this transaction, and that can be determined by checking
         * the pEnvoyReq->dynamic boolean flag. This flag is cleared at the end
         * of each transaction (by ospf_envoy_clearBuffer()) and it is only set
         * if a buffer is allocated within the context of the current transaction.
         */
        if ( (pEnvoyReq->pOctetBuf != NULL) && (pEnvoyReq->dynamic == TRUE) )
        {
            SNMP_memory_free( pEnvoyReq->pOctetBuf );
            pEnvoyReq->pOctetBuf = NULL;
        }

        ospf_envoy_clearBuffer( pEnvoyReq );
        ospf_envoy_processGetRespError( pktp, vbp, reqType, request.error );
        return;
    }

    /* send the request to MIB API */
    rc = ospfMapiGetLsdb( &request, reqType );
    if ( rc == ERROR )
    {
        
        if ( (pEnvoyReq->pOctetBuf != NULL) && (pEnvoyReq->dynamic == TRUE) )
        {
            SNMP_memory_free( pEnvoyReq->pOctetBuf );
            pEnvoyReq->pOctetBuf = NULL;
        }

        ospf_envoy_clearBuffer( pEnvoyReq );
        for ( ; vbp ; vbp = vbp->vb_link )
        {
            if ( request.error == MAPI_INVALID_INSTANCE )
            {
                if ( reqType == MAPI_GET_NEXT )
                    nextproc_no_next( pktp, vbp );
                else
                    getproc_nosuchins( pktp, vbp );
            }
            else
            {
                if ( reqType == MAPI_GET_NEXT )
                    nextproc_error( pktp, vbp, mApi2EnvoyErrorGet( request.error) );
                else
                    getproc_error( pktp, vbp, mApi2EnvoyErrorGet( request.error) );
            }
        }
        return;
    }

    /* retrieve all the values from the request structure */
    ospf_envoy_processGetResp( vbp, pktp, pEnvoyReq, &request, reqType,
                               ospfMapiLsdb_OID_OFFSET );
    return;
}

/****************************************************************************************
* ospfEnvoy_getIf - generic get routine for ospfIfTable
*
* This is the generic get routine for ospfIfTable. It query the mib api for the table
* row in which the requested object instances can be found. The behavior of the mib api
* is based on request type, either GET or GET_NEXT. If it is a GET_NEXT request, the
* smallest instance that is larger than the given tcount/tlist will be returned.
*
* RETURNS: N/A
*
* NOMANUAL
*/
LOCAL void ospfEnvoy_getIf( int tcount, OIDC_T *tlist, SNMP_PKT_T *pktp, VB_T *vbp,
                            mApiReqType_t reqType )
{
    mApiRequest_t  request;
    VB_T           *group_vbp;
    char           authKey[4];
    STATUS         rc;

    if ( ospfEnvoy_init_check( pktp, vbp, reqType ) == ERROR )
        return;

    /* the ospfEnvoy_build_getRequest() expects the buffer for the octet string to
     * be allocated by the caller. Loop through the varbinds and determine if
     * there is an object whose type is octet string.
     */
    for ( group_vbp = vbp ; group_vbp != NULL; group_vbp = group_vbp->vb_link )
    {
        if ( (group_vbp->vb_ml.ml_leaf->expected_tag == VT_STRING) ||
             (group_vbp->vb_ml.ml_leaf->expected_tag == VT_OPAQUE) )
        {
            if ( group_vbp->vb_ml.ml_last_match != LEAF_ospfIfAuthKey )
                continue;

            /* for ospfIfTable, ospfIfAuthKey is the only object using octet string.
             * RFC1850 requires that the ospfIfAuthKey when read, will always returns
             * an octet string of length zero. Statically allocate an array of ulong_t
             * to satisfy the request
             */
            memset( authKey, 0, sizeof(authKey) );
            pEnvoyReq->pOctetBuf = authKey;
            pEnvoyReq->octetBufLen = sizeof(authKey);

            /* mark this buffer as static */
            pEnvoyReq->dynamic = FALSE;
            break;  /* there can be only one octet string object in a row */
        }
    }

    /* build the MIB API request message */
    memset( (char *)&request, 0, sizeof(mApiRequest_t) );
    rc = ospf_envoy_buildGetReq( tcount, tlist, vbp, pEnvoyReq, &request,
                                 ospfMapiIf_OID_OFFSET );
    if ( rc == ERROR )
    {
        ospf_envoy_clearBuffer( pEnvoyReq );
        ospf_envoy_setGenError( pktp, vbp, reqType );
        return;
    }

    /* send the request to MIB API */
    rc = ospfMapiGetIf( &request, reqType );
    if ( rc == ERROR )
    {
        ospf_envoy_clearBuffer( pEnvoyReq );
        ospf_envoy_processGetRespError( pktp, vbp, reqType, request.error );
        return;
    }

    /* retrieve all the values from the request structure */
    ospf_envoy_processGetResp( vbp, pktp, pEnvoyReq, &request, reqType,
                               ospfMapiIf_OID_OFFSET );
    return;
}

/***************************************************************************************
* ospfEnvoy_setIf - generic set function for ospfIfTable
*
* This routine is a generic set function for ospfIfTable. It invokes by testproc and
* setproc to test and set objects in varbinds.
*
* RETURNS: N/A
*
* NOMANUAL
*/
LOCAL void ospfEnvoy_setIf( int tcount, OIDC_T *tlist, SNMP_PKT_T *pktp, VB_T *vbp,
                            mApiReqType_t reqType )
{
    mApiRequest_t  request;
    VB_T           *group_vbp;
    STATUS         rc;

    if ( tcount != ospfIfEntry_INST_LEN )
    {
        ospf_envoy_setNoSuchNameError( pktp, vbp, reqType );
        return;
    }

    if ( ospfEnvoy_init_check( pktp, vbp, reqType ) == ERROR )
        return;

    /* use the data provided by the varbinds directly. This eliminates the need
     * to copy the data from varbinds to locally allocated buffer.
     */
    rc = ospf_envoy_buildSetReq( tcount, tlist, pktp, vbp, pEnvoyReq, &request, reqType,
                                 ospfMapiIf_OID_OFFSET );
    if ( rc == ERROR )
    {
        ospf_envoy_setGenError( pktp, vbp, reqType );
        return;
    }

    /* send the request to OSPF MIB API for processing */
    rc = ospfMapiSetIf( &request, reqType );
    if ( rc == ERROR )
    {
        for (group_vbp = vbp; group_vbp != NULL; group_vbp = group_vbp->vb_link )
        {
            group_vbp->vb_priv = NULL;
            if ( reqType == MAPI_TEST )
                testproc_error( pktp, group_vbp, mApi2EnvoyErrorGet( request.error));
            else
            {
                /* tell envoy to start the undo operation. Envoy should call the
                 * undo routine immediately once the setproc_error indicates
                 * the set process has failed.
                 */
                group_vbp->undoproc = ospfEnvoy_undo; /* our undo routine */

                /* issue a fake undo request to mib api so that it can reset its
                 * internal transaction counters.
                 */
                ospfMapiSetIf( &request, MAPI_UNDO );
                setproc_error( pktp, group_vbp, mApi2EnvoyErrorGet( request.error));
            }
        }

        /* tell MIB API we have completed the transaction */
        ospfMapiSetIf( &request, MAPI_COMPLETE );

        ospf_envoy_clearBuffer( pEnvoyReq );
        if (  (pEnvoyReq->dynamic == TRUE) && (pEnvoyReq->pOctetBuf != NULL) )
        {
            SNMP_memory_free( pEnvoyReq->pOctetBuf );
            pEnvoyReq->pOctetBuf = NULL;
        }
        return;
    }

    if ( reqType == MAPI_TEST )
    {
        /* stash the looked up information here for the setproc. Although Envoy
         * provide vb_priv in each varbind, only stash it to the first varbind.
         * MIB API only allow one cookie per request, and we only need one anyhow
         */
        vbp->vb_priv = (void *)request.pReqCookie;
    }

    /* tell MIB API we have completed the transaction */
    if ( reqType == MAPI_COMMIT )
        ospfMapiSetIf( &request, MAPI_COMPLETE );

    /* make the varbind as done and check for any exception in varbinds */
    ospf_envoy_markVarbind( vbp, pktp, &request, reqType );
    ospf_envoy_clearBuffer( pEnvoyReq );
    if (  (pEnvoyReq->dynamic == TRUE ) && (pEnvoyReq->pOctetBuf != NULL) )
    {
        SNMP_memory_free( pEnvoyReq->pOctetBuf );
        pEnvoyReq->pOctetBuf = NULL;
    }

    return;
}

/****************************************************************************************
* ospfEnvoy_getIfMetric - generic get routine for ospfIfMetricTable
*
* This is the generic get routine for ospfIfMetricTable. It query the mib api for the
* table row in which the requested object instances can be found. The behavior of the mib
* api is based on request type, either GET or GET_NEXT. If it is a GET_NEXT request, the
* smallest instance that is larger than the given tcount/tlist will be returned.
*
* RETURNS: N/A
*
* NOMANUAL
*/
LOCAL void ospfEnvoy_getIfMetric( int tcount, OIDC_T *tlist, SNMP_PKT_T *pktp, VB_T *vbp,
                                  mApiReqType_t reqType )
{
    mApiRequest_t  request;
    STATUS         rc;