dhcpclib.c

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    int offset;
    LEASE_DATA *        pLeaseData = NULL;
    STATUS result = OK;

    /*
     * Use the cookie to access the lease-specific data structures.  For now,
     * just typecast the cookie.  This translation could be replaced with a more
     * sophisticated lookup at some point.
     */

    pLeaseData = (LEASE_DATA *)pCookie;

    for (offset = 0; offset < dhcpcMaxLeases; offset++)
        if (dhcpcLeaseList [offset] != NULL &&
                dhcpcLeaseList [offset] == pLeaseData)
            break;

    if (offset == dhcpcMaxLeases)
        {
        errno = S_dhcpcLib_BAD_COOKIE;
        return (ERROR);
        }

    if (!dhcpcInitialized || !pLeaseData->initFlag)
        {
        errno = S_dhcpcLib_NOT_INITIALIZED;
        return (ERROR);
        }

    /*
     * Use the cookie to access the lease-specific data structures.  For now,
     * just typecast the cookie.  This translation could be replaced with a more
     * sophisticated lookup at some point.
     */

    pLeaseData = (LEASE_DATA *)pCookie;

    /* Construct and send a release request to the client monitor task.  */

    result = dhcpcEventAdd (DHCP_USER_EVENT, DHCP_USER_RELEASE,
                            pLeaseData, FALSE);

    return (result);
    }

/*******************************************************************************
*
* dhcpcShutdown - disable DHCP client library
*
* This routine schedules the lease monitor task to clean up memory and exit,
* after releasing all currently active leases.  The network boot device
* will be disabled if the DHCP client was used to obtain the VxWorks boot 
* parameters and the resulting lease is still active.  Any other interfaces 
* using the addressing information from leases set for automatic configuration
* will also be disabled.  Notification of a disabled interface will not occur
* unless an event hook has been installed.  After the processing started by
* this request completes, the DHCP client library is unavailable until 
* restarted with the dhcpcLibInit() routine.
*
* RETURNS: OK if shutdown scheduled, or ERROR otherwise.
*
* ERRNO: S_dhcpcLib_NOT_INITIALIZED
* 
*/

STATUS dhcpcShutdown (void)
    {
    STATUS 	result;

    if (!dhcpcInitialized)
        {
        errno = S_dhcpcLib_NOT_INITIALIZED;
        return (ERROR);
        }

    /* Construct and send a shutdown request to the client monitor task.  */

    result = dhcpcEventAdd (DHCP_USER_EVENT, DHCP_USER_SHUTDOWN, NULL, FALSE);

    return (result);
    }

/*******************************************************************************
*
* dhcpcOptionGet - retrieve an option provided to a client and store in a buffer
*
* This routine retrieves the data for the specified <option>, if present
* for the lease indicated by <pCookie>.  The data is stored in the provided 
* buffer, whose length must be specified.  If the <option> is found, the amount 
* of data available is stored in the location referenced by the <pLength> 
* parameter.  The option is not available if the DHCP client is not in the 
* bound state or if the server did not provide it.  After returning, the 
* provided buffer may contain IP addresses stored in network byte order.  All 
* other numeric values are stored in host byte order.  See RFC 1533 for specific
* details on the data retrieved. 
* 
* RETURNS: OK if option available, or ERROR otherwise.
*
* ERRNO: S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED, S_dhcpcLib_NOT_BOUND,
*  S_dhcpcLib_OPTION_NOT_PRESENT
*
* SEE ALSO
* dhcpcOptionSet()
*/

STATUS dhcpcOptionGet
    (
    void * 	pCookie, 	/* identifier returned by dhcpcInit() */
    int 	option,		/* RFC 1533 option tag */
    int * 	pLength, 	/* size of provided buffer and data returned */
    char *	pBuf 		/* location for option data */
    )
    {
    char *	pData;
    int  	amount;
    int 	limit;
    int 	offset;
    LEASE_DATA * 	pLeaseData;

    limit = *pLength;

    /*
     * Use the cookie to access the lease-specific data structures.  For now,
     * just typecast the cookie.  This translation could be replaced with a more
     * sophisticated lookup at some point.
     */

    pLeaseData = (LEASE_DATA *)pCookie;

    for (offset = 0; offset < dhcpcMaxLeases; offset++)
        if (dhcpcLeaseList [offset] != NULL && 
                dhcpcLeaseList [offset] == pLeaseData)
            break;

    if (offset == dhcpcMaxLeases)
        {
        errno = S_dhcpcLib_BAD_COOKIE;
        return (ERROR);
        }

    if (!dhcpcInitialized || !pLeaseData->initFlag)
        {
        errno = S_dhcpcLib_NOT_INITIALIZED;
        return (ERROR);
        }

    /* Check if client is bound.  */

    semTake (dhcpcMutexSem, WAIT_FOREVER);
    if (!pLeaseData->leaseGood)
        {
        errno = S_dhcpcLib_NOT_BOUND;
        semGive (dhcpcMutexSem);
        return (ERROR);
        }
    semGive (dhcpcMutexSem);

    /* Check if requested parameter is available.  */

    if (!ISSET (pLeaseData->dhcpcParam->got_option, option))
        {
        errno = S_dhcpcLib_OPTION_NOT_PRESENT;
        return (ERROR);
        }

    /* Find the location of option data */

    pData = dhcpcOptionFind (pLeaseData, option, &amount);
    if (pData == NULL)
        {
        errno = S_dhcpcLib_OPTION_NOT_PRESENT;
        return (ERROR);
        }

    if (amount == 0)
        {
        /* Requested parameter not provided by server - no data returned.  */

        *pLength = 0;
        return (OK);
        }

    if (amount < limit)         /* Adjust for size of option data.  */
        limit = amount;
 
    bcopy (pData, pBuf, limit);
    *pLength = limit;

    return (OK);
    }

/*******************************************************************************
*
* dhcpcServerGet - retrieve the current DHCP server
*
* This routine returns the DHCP server that supplied the configuration
* parameters for the lease specified by the <pCookie> argument.  This 
* information is available only if the lease is in the bound state.
*
* RETURNS: OK if in bound state and server available, or ERROR otherwise.
*
* ERRNO: S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED, S_dhcpcLib_NOT_BOUND
*/

STATUS dhcpcServerGet
    (
    void * 		pCookie, 	/* identifier returned by dhcpcInit() */
    struct in_addr * 	pServerAddr 	/* location for address of server */
    )
    {
    int offset;
    LEASE_DATA * 	pLeaseData;
    STATUS 		result = OK;

    /*
     * Use the cookie to access the lease-specific data structures.  For now,
     * just typecast the cookie.  This translation could be replaced with a more
     * sophisticated lookup at some point.
     */

    pLeaseData = (LEASE_DATA *)pCookie;

    for (offset = 0; offset < dhcpcMaxLeases; offset++)
        if (dhcpcLeaseList [offset] != NULL &&
                dhcpcLeaseList [offset] == pLeaseData)
            break;

    if (offset == dhcpcMaxLeases)
        {
        errno = S_dhcpcLib_BAD_COOKIE;
        return (ERROR);
        }

    if (!dhcpcInitialized || !pLeaseData->initFlag)
        {
        errno = S_dhcpcLib_NOT_INITIALIZED;
        return (ERROR);
        }

    semTake (dhcpcMutexSem, WAIT_FOREVER);
    if (!pLeaseData->leaseGood)
        result = ERROR;
    semGive (dhcpcMutexSem);

    if (result == ERROR)
        {
        errno = S_dhcpcLib_NOT_BOUND;
        return (ERROR);
        }

    if (pLeaseData->dhcpcParam->server_id.s_addr != 0)
        bcopy ( (char *)&pLeaseData->dhcpcParam->server_id, 
               (char *)pServerAddr, sizeof (struct in_addr));
    else 
        result = ERROR;

    return (result);
    }

/*******************************************************************************
*
* dhcpcTimerGet - retrieve current lease timers
*
* This routine returns the number of clock ticks remaining on the timers
* governing the DHCP lease specified by the <pCookie> argument.  This 
* information is only available if the lease is in the bound state.
* Therefore, this routine will return ERROR if a BOOTP reply was accepted.
*
* RETURNS: OK if in bound state and values available, or ERROR otherwise.
*
* ERRNO: S_dhcpcLib_BAD_COOKIE, S_dhcpcLib_NOT_INITIALIZED, S_dhcpcLib_NOT_BOUND, 
*  S_dhcpcLib_OPTION_NOT_PRESENT, S_dhcpcLib_TIMER_ERROR
*/

STATUS dhcpcTimerGet
    (
    void * 	pCookie, 	/* identifier returned by dhcpcInit() */
    int * 	pT1, 		/* time until lease renewal */
    int * 	pT2 		/* time until lease rebinding */
    )
    {
    int 	offset;
    time_t	current = 0;
    long	timer1;
    long	timer2;
    LEASE_DATA *        pLeaseData;
    STATUS 		result = OK;

    /*
     * Use the cookie to access the lease-specific data structures.  For now,
     * just typecast the cookie.  This translation could be replaced with a more
     * sophisticated lookup at some point.
     */

    pLeaseData = (LEASE_DATA *)pCookie;

    for (offset = 0; offset < dhcpcMaxLeases; offset++)
        if (dhcpcLeaseList [offset] != NULL &&
                dhcpcLeaseList [offset] == pLeaseData)
            break;

    if (offset == dhcpcMaxLeases)
        {
        errno = S_dhcpcLib_BAD_COOKIE;
        return (ERROR);
        }

    if (!dhcpcInitialized || !pLeaseData->initFlag)
        {
        errno = S_dhcpcLib_NOT_INITIALIZED;
        return (ERROR);
        }

    if (pLeaseData->leaseType == DHCP_BOOTP)
        {
#ifdef DHCPC_DEBUG
        logMsg ("No timer values: BOOTP reply accepted.\n", 0, 0, 0, 0, 0, 0);
#endif
        errno = S_dhcpcLib_OPTION_NOT_PRESENT;
        return (ERROR);
        }

    if (time (&current) == -1)
        {
#ifdef DHCPC_DEBUG
        logMsg ("time() error in dhcpTimerGet().\n", 0, 0, 0, 0, 0, 0);
#endif
        errno = S_dhcpcLib_TIMER_ERROR;
        return (ERROR);
        }

    semTake (dhcpcMutexSem, WAIT_FOREVER);
    if (!pLeaseData->leaseGood)
        result = ERROR;
    semGive (dhcpcMutexSem);

    if (result == ERROR)
        {
        errno = S_dhcpcLib_NOT_BOUND;
        return (ERROR);
        }

    timer1 = pLeaseData->dhcpcParam->lease_origin + 
                 pLeaseData->dhcpcParam->dhcp_t1 - current;
    timer2 = pLeaseData->dhcpcParam->lease_origin + 
                 pLeaseData->dhcpcParam->dhcp_t2 - current;

    if (timer1 < 0)
        timer1 = 0;   
    if (timer2 < 0)
        timer2 = 0;

    *pT1 = timer1 * sysClkRateGet();
    *pT2 = timer2 * sysClkRateGet();

    return (OK);
    }

/*******************************************************************************
*
* dhcpcParamsGet - retrieve current configuration parameters
*
* This routine copies the current configuration parameters for the lease
* specified by the <pCookie> argument to the user-supplied structure.  That 
* structure, defined in dhcp/dhcpc.h, should contain non-NULL pointers to 
* indicate the parameters of interest.  All other values within the structure 
* must be set to 0 before calling the routine.  The requested information is 
* only retrieved if the specified lease is in the bound state and knows that 
* its parameters are good.
* 
* Many of the parameters within the user-supplied structure use one of the 
* following secondary data types: struct in_addrs, struct u_shorts, and 
* struct vendor_list.  Each of those structures accepts a length designation 
* and a data pointer.  For the first two data types, the 'num' member indicates 
* the size of the buffer in terms of the number of underlying elements.  For 
* example, the STATIC_ROUTE option returns one or more IP address pairs.  So, 
* setting the 'num' member to 2 in the static_route entry would indicate that 
* the corresponding buffer contained 16 bytes.  By contrast, the 'len' member 
* in the struct 'vendor_list' data type consists