/*********************************************************************
 *
 *  Zero Configuration (Zeroconf) IPV4 Link Local Addressing
 *  Module for Microchip TCP/IP Stack
 *
 *********************************************************************
 * FileName:        ZeroconfLinkLocal.c
 * Dependencies:    IP, ARP
 * Processor:       PIC24F, PIC24H, dsPIC30F, dsPIC33F, PIC32
 * Compiler:        Microchip C32 v1.05 or higher
 *					Microchip C30 v3.12 or higher
 * Company:         Microchip Technology, Inc.
 *
 * Software License Agreement
 *
 * Copyright (C) 2009-2010 Microchip Technology Inc.  All rights
 * reserved.
 *
 * Microchip licenses to you the right to use, modify, copy, and
 * distribute:
 * (i)  the Software when embedded on a Microchip microcontroller or
 *      digital signal controller product ("Device") which is
 *      integrated into Licensee's product; or
 * (ii) ONLY the Software driver source files ENC28J60.c, ENC28J60.h,
 *		ENCX24J600.c and ENCX24J600.h ported to a non-Microchip device
 *		used in conjunction with a Microchip ethernet controller for
 *		the sole purpose of interfacing with the ethernet controller.
 *
 * You should refer to the license agreement accompanying this
 * Software for additional information regarding your rights and
 * obligations.
 *
 * THE SOFTWARE AND DOCUMENTATION ARE PROVIDED "AS IS" WITHOUT
 * WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT
 * LIMITATION, ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * MICROCHIP BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES, LOST PROFITS OR LOST DATA, COST OF
 * PROCUREMENT OF SUBSTITUTE GOODS, TECHNOLOGY OR SERVICES, ANY CLAIMS
 * BY THIRD PARTIES (INCLUDING BUT NOT LIMITED TO ANY DEFENSE
 * THEREOF), ANY CLAIMS FOR INDEMNITY OR CONTRIBUTION, OR OTHER
 * SIMILAR COSTS, WHETHER ASSERTED ON THE BASIS OF CONTRACT, TORT
 * (INCLUDING NEGLIGENCE), BREACH OF WARRANTY, OR OTHERWISE.
 *
 *
 * Author               Date        Comment
 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 * Pradeep Reddy        01 Mar 2009 Initial
 * Pradeep Reddy        12 May 2009 Enhancements and fixes
 * Pradeep Reddy        13 May 2010 Code documentation and cleanup
 * Brad Rex             05 Apr 2010 Updated for MRF24WB0M.
 ********************************************************************/
#define __Zeroconf__Link_Local_C

#include "TCPIP Stack/TCPIP.h"

#define TICK DWORD

#if defined(STACK_USE_ZEROCONF_LINK_LOCAL)
#include "TCPIP Stack/ZeroconfLinkLocal.h"
//#include "ZGCustomize.h"

extern void DisplayIPValue(IP_ADDR IPVal);

/* Constant to cross-check whether
 * DHCP Clinet is configured to use */
#if defined(STACK_USE_DHCP_CLIENT)
const BYTE g_zcll_dhcp_client = 1;
#else
const BYTE g_zcll_dhcp_client = 0;
#endif

/* constants from RFC2937, section 9 */
#define PROBE_WAIT           1 /*second  (initial random delay)              */
#define PROBE_MIN            1 /*second  (minimum delay till repeated probe) */
#define PROBE_MAX            2 /*seconds (maximum delay till repeated probe) */
#define PROBE_NUM            3 /*         (number of probe packets)          */
#define ANNOUNCE_WAIT        2 /*seconds  (delay before announcing)          */
#define ANNOUNCE_NUM         2 /*        (number of announcement packets)    */
#define ANNOUNCE_INTERVAL    2 /*seconds (time between announcement packets) */
#define MAX_CONFLICTS       10 /*        (max conflicts before rate limiting)*/
#define RATE_LIMIT_INTERVAL 60 /*seconds (delay between successive attempts) */
#define DEFEND_INTERVAL     10 /*seconds (min. wait between defensive ARPs)  */

/* compilation constants */
#define IPV4_LLBASE 0xa9fe0100 /* 169.254.1.0 */

/* ARP  States Enum */
typedef enum _ARPState{
	ARPProbe = 0,
	ARPClaim,
	ARPDefend
} ARP_STATE;

/* Link-Local States Enum */
typedef enum _ZeroconfLLState
{
	SM_INIT = 0,
	SM_INTF_NOT_PRESENT,
	SM_INTF_NOT_CONNECTED,
	SM_DHCP_PRESENT,
	SM_ADDR_INIT,
	SM_ADDR_PROBE,
	SM_ADDR_CLAIM,
	SM_ADDR_DEFEND,	
	SM_ADDR_RELEASE,
} ZCLL_STATE;

/* Required for Tracking DHCP events */
typedef enum __zcll_dhcp_substate {
	ZCLL_DHCP_INIT = 0,
	ZCLL_DHCP_PHASE_1,
	ZCLL_DHCP_PHASE_2,
}ZCLL_DHCP_SUBSTATE;

/* ARP-Packet Types defined in RFC 2937 */
typedef enum arp_pkt_type {
	ARP_REQUEST_TYPE = 0,
	ARP_PROBE_TYPE,
	ARP_CLAIM_TYPE,
	ARP_DEFEND_TYPE,
	ARP_RESPONSE_TYPE,
	UNKNOWN_TYPE,
}ARP_PKT_TYPE;

/* Flags for the ZCLL State Machine */
typedef union _ZCLL_FLAGS
{
    struct
    {
        unsigned char bIsIntfPresent : 1;		// Whether or not Interface is present
        unsigned char bIsDHCPPresent : 1;		// Whether or not DHCP Client is enabled & 
												// DHCP server is detected
		unsigned char bIsConnected : 1;			// Indicates if WiFi interface is connected
		unsigned char probe_conflict :1 ;		// Conflict When selecting IP-addr
		unsigned char late_conflict : 1;		// Conflict When using IP-addr
    } bits;
    BYTE Val;
} ZCLL_FLAGS;

/**************** Global Declarations ***************/
ZCLL_STATE zcll_state = SM_INIT;
ZCLL_DHCP_SUBSTATE zcll_dhcp_substate =ZCLL_DHCP_INIT;
static ZCLL_FLAGS zcll_flags = {{0x00}};

static IP_ADDR temp_IP_addr;	// Temporary IP address before checking uniquness
#ifdef STACK_CLIENT_MODE
static MAC_ADDR temp_MAC_addr;  // Temporary MAC address
#endif
static BYTE probe_count = 0;
static BYTE conflict_count = 0; 
static BYTE announce_count = 0;

static BOOL bDefaultIPTried = FALSE;

static CHAR arp_reg_id;

/***************** Forward Declarations **************/
void ZeroconfARPPktNotify (DWORD SenderIPAddr, DWORD TargetIPAddr, 
                           MAC_ADDR* SenderMACAddr, 
                           MAC_ADDR* TargetMACAddr, BYTE op_req);
static struct arp_app_callbacks callbacks = 
{
	.ARPPkt_notify  = ZeroconfARPPktNotify,
};

//rex#if 0
//rextZGVoidReturn 
//rexZeroconfIndicate(tZGU8 type, tZGDataPtr fourByteHeader, tZGDataPtr pBuf, tZGU16 len)
//rex{
//rex    tZGU16 status;
//rex    
//rex    switch(type)
//rex    {
//rex    	case kZGMgtIndDisconnect:
//rex        	/* A deauth indication occurs when the AP has announced
//rex             * to our chip that the connection is no longer valid.  It becomes
//rex             * the responsibility of the wifiManager to determine what to do
//rex             * in that situation */
//rex			INFO_ZCLL_PRINT("Zeroconf-Callback: Disconnect Event Notification \r\n");
//rex            zcll_flags.bits.bIsConnected = 0;   
//rex        break;
//rex        
//rex    case kZGMgtIndConnStatus:
//rex    
//rex        status = (fourByteHeader[0] << 8) | fourByteHeader[1];
//rex        if (status == kZGConnStatusFound)
//rex        {
//rex            //APPCXT.bConnLost = 0;
//rex            //APPCXT.bConnFound = 1;
//rex			zcll_flags.bits.bIsConnected = 1;
//rex        }
//rex        break;
//rex        
//rex    default:
//rex        /* error condition un-recognized type */
//rex        break;
//rex    }
//rex    
//rex}
//rex#endif

DWORD zcll_rand(void)
{
	return TickGet();
}

/***************************************************************
  Function:
	static void ZeroconfStateMachineReset(void)

  Summary:
	Resets Zeroconf's Link-Local state-machine
    
  Description:
	This function resets the state-machine of Link-Local module.
    This is invoked in the initalization and when a address-conflict
    is detected.   

  Parameters:
	None 

  Returns:
  	None
  ***************************************************************/
#if 0
#define ZeroconfStateMachineReset() \
{probe_count = zcll_flags.bits.late_conflict = zcll_flags.bits.probe_conflict =0;}
#endif

static void ZeroconfStateMachineReset(BOOL bResetProbeCount)
{
	if (bResetProbeCount)
	{
		probe_count = 0;
	}
	zcll_flags.bits.late_conflict = 0; 
	
	//conflict_count = 0;
	//zcll_flags.bits.probe_conflict = 0;
}


/***************************************************************
  Function:
	void ARPAction(IP_ADDR SrcIPAddr,IP_ADDR DestIPAddr ,BYTE op_req,ARP_STATE ARPAction)

  Summary:
     a).ARPProbe:
	  Sends out the ARP-probe packet.
     b).ARPClaim:
	  Sends out the ARP-Claim packet.
     c).ARPDefend:
         Sends out the ARP-Defend packet, when a address-conflict is detected.
    
  Description:


    a).ARPProbe:
	This function is used to send out the ARP-Probe packet to check
    the uniquness of selected IP-address in private space(169.254.x.x)

    This function makes use of ARPSendPkt User-API exposed by ARP 
    module. 

    ARP-Probe Packet:
	  ARP-Request
	  sender IP address: 0.0.0.0
	  sender HW address: Self MAC address
	  target IP address: <probe addr> (Chosen IP-address 169.254.x.x)
	  target HW address: FF:FF:FF:FF:FF:FF
	  
    b).ARPClaim:
 	This function is used to send out the ARP-Claim packet to finalize
    the uniquness of selected IP-address in private space(169.254.x.x).
    This claim packet is final-step in decision making of selected IP-
    address.

    This function makes use of ARPSendPkt User-API exposed by ARP 
    module. 

    ARP-Probe Packet:
	  ARP-Request
	  sender IP address: <claim addr> (Chosen IP-address 169.254.x.x)
	  sender HW address: Self MAC address
	  target IP address: <claim addr> (Chosen IP-address 169.254.x.x)
	  target HW address: FF:FF:FF:FF:FF:FF
	  
    c).ARPDefend:
    	This function is used to send out the ARP-Defend packet to defend
    the selected IP-address. When a conflicting ARP-packet (Probe or
    Claim) is observed on local network ARP-defend packet will be sent
    out to announe its authority of owning IP-address.

    This function makes use of ARPSendPkt User-API exposed by ARP 
    module. 

    ARP-Probe Packet:
	  ARP-Response
	  sender IP address: <claim addr> (Chosen IP-address 169.254.x.x)
	  sender HW address: Self MAC address
	  target IP address: <claim addr> (Chosen IP-address 169.254.x.x)
	  target HW address: FF:FF:FF:FF:FF:FF

  Parameters:
	None 

  Returns:
  	None
  ***************************************************************/

void ARPAction(DWORD SrcIPAddr,DWORD DestIPAddr ,BYTE op_req,ARP_STATE ARPAction)
{
	BOOL rc;

	rc = ARPSendPkt( SrcIPAddr, DestIPAddr,op_req);

#if defined ( INFO_ZCLL )
	if(rc == FALSE)
	{
         switch (ARPAction)
         {
		 	case ARPProbe:
				INFO_ZCLL_PRINT("ARPProbe: Error in sending out ARP-Probe pkt \n");
			    break;
		 	case ARPClaim:
				INFO_ZCLL_PRINT("ARPClaim: Error in sending out ARP-Claim pkt \n");
			    break;
		 	case ARPDefend:
				INFO_ZCLL_PRINT("ARPDefend: Error in sending out ARP-Defend pkt \n");
			    break;
         }		
	}
#endif
}

/***************************************************************
  Function:
	ARP_PKT_TYPE FindARPPktType (DWORD SrcIPAddr, DWORD DestIPAddr, 
                                 BYTE op_req)

  Summary:
	Finds the Type of ARP-Packet based on the Source IP-address,
    Destination IP-address and operation-request.
    
  Description:
	This function is used to find out the ARP-packet type. When ARP
    module passes up a ARP-packet to Zeroconf Link-Local module, it 
    parses contents and finds the packet-type (like ARP-Probe, ARP-
    Claim, ARP-Defend, or generic ARP-request/response)    

  Parameters:
	SrcIPAddr    - Source IP-Address
    DestIPAddr   - Destination IP-Address
    op_req       - Operation-Request (ARP-Request/Response)

  Returns:
  	ARP_PKT_TYPE - Type of ARP-Packet (Probe, Claim, Defend or 
                    generic ARP-request/response)
  ***************************************************************/
ARP_PKT_TYPE FindARPPktType (DWORD SrcIPAddr, DWORD DestIPAddr,BYTE op_req)
{
	if(op_req == ARP_REQ)
	{
		if(SrcIPAddr == 0x0)
			return ARP_PROBE_TYPE;
		else if (SrcIPAddr == DestIPAddr)
			return ARP_CLAIM_TYPE;
		else 
			return ARP_REQUEST_TYPE;

	}

	else if(op_req == ARP_RESP)
	{
		if(SrcIPAddr == DestIPAddr)
			return ARP_DEFEND_TYPE;
		else
			return ARP_RESPONSE_TYPE;
	}
	
	else
		return UNKNOWN_TYPE;
}
	
/***************************************************************
  Function:
	void ZeroconfARPPktNotify (DWORD SenderIPAddr, DWORD TargetIPAddr, 
                           MAC_ADDR* SenderMACAddr, 
                           MAC_ADDR* TargetMACAddr, BYTE op_req)

  Summary:
	Callback registered with ARP-Module. This gets invoked from ARP-
    module and runs in the same context.
    
  Description:
	This function is registered as a callback with ARP-module to get 
    notified about incoming Packet-events. Based on the type of packet
    received and Link-Local current state, appropriate action will be 
    taken. To find the type of ARP-Packet this function makes use of 
    FindARPPktType routine.

    Primary purpose of this function is to decipher the ARP-Packet rxed
    and check whether its leading to a conflict with the selected IP-
    address.

    Two types of conflicts are defined: Probe-Conflict and Late-Conflict
    If the current state of Link-Local is Probe/Claim and a conflict is
    detected its called "Probe-Conflict"
    If the current state of Link-Local is Defend-state and a conflict is
    detected its called "Late-Conflict"

  Parameters:
	SenderIPAddr    - Sender IP-Address
    TargetIPAddr    - Target IP-Address
    SenderMACAddr   - Sender MAC-Address
    TargetMACAddr   - Target MAC-Address
    op_req          - Operation-Request (ARP-Request/Response)
	
  Returns:
  	None
  ***************************************************************/	
void ZeroconfARPPktNotify (DWORD SenderIPAddr, DWORD TargetIPAddr, 
                           MAC_ADDR* SenderMACAddr, 
                           MAC_ADDR* TargetMACAddr, BYTE op_req)
{
	ARP_PKT_TYPE pkt_type;

	pkt_type = FindARPPktType (SenderIPAddr, TargetIPAddr, op_req);

	if(pkt_type == UNKNOWN_TYPE)
		return; // Can't hit this

	switch (zcll_state)
	{
	case SM_ADDR_PROBE:
	case SM_ADDR_CLAIM:
		{
			switch(pkt_type)
			{
			case ARP_PROBE_TYPE:
			case ARP_CLAIM_TYPE:
			case ARP_DEFEND_TYPE:
				if(temp_IP_addr.Val == TargetIPAddr ) // Probe-Conflict
				{
					if(memcmp(SenderMACAddr, &AppConfig.MyMACAddr, 6)) 
					{
						DEBUG_ZCLL_PRINT("ARPPktNotify: Somebody has initiated " \
							"the procedure to use same Addr.\r\n");

						zcll_flags.bits.probe_conflict =1;
					}
				}
				break;

			case ARP_RESPONSE_TYPE:
				/* Some-body has been using probed addr
				* We need to choose different Address */
				if(temp_IP_addr.Val == SenderIPAddr) 
				{
					DEBUG_ZCLL_PRINT("ARPPktNotify: Some-body has responded for " \
						"probed IP-addr \r\n");

					zcll_flags.bits.probe_conflict =1;	
				}
				break;
			default:
				break;
			}
		}
		break;

	case SM_ADDR_DEFEND:
		{
			if(AppConfig.MyIPAddr.Val == SenderIPAddr)
			{
				if(memcmp(SenderMACAddr, &AppConfig.MyMACAddr, 6)) 
				{
					DEBUG_ZCLL_PRINT("ARPPktNotify: Some-one has started using" \
						" our IP-address \r\n");

					zcll_flags.bits.late_conflict = 1;
				}
			}
		}
		break;

	default:
		break; // Nothing to do in other states
	}

}

/***************************************************************
  Function:
	static void zcll_seed_random()

  Summary:
	Seeds the Random-Number generator with Last four bytes of MAC-
    address & current-time.
    
  Description:
	This function is used to seed the random-number generator. To get
    better uniquness in random-number, last four bytes of MAC-address 
    is used as seed. Though the MAC-address is unique, the first 3
    bytes represent the manufacturer, which will be same for all the 
    Network-Interface cards from same manufacturer.

    To add more randomness the current-time is also added as seed. The
    current-time alone can't be used as seed. Because there's a fair
    chance that all the devices in local-area network might be powered
    up at the same-time, then which leads to conflict.

    So combination of MAC-Address and current-time is good seed for a
    random-number generator.
        
  Parameters:
	None

  Returns:
  	None
  ***************************************************************/
#if 0
static void zcll_seed_random()
{
	DWORD_VAL temp;
	DWORD tick = TickGet();
	temp.v[3] = AppConfig.MyMACAddr.v[2];
	temp.v[2] = AppConfig.MyMACAddr.v[3];
	temp.v[1] = AppConfig.MyMACAddr.v[4];
	temp.v[0] =	AppConfig.MyMACAddr.v[5];
	srand( temp.Val + tick ); 
}
#endif

/***************************************************************
  Function:
	void ZeroconfLLInitialize(void)

  Summary:
	Initialization routine for Zeroconf Link-Local state-machine.
    
  Description:
    This is initialization function for Zeroconf Link-Local and 
    invoked from initialization portion of Main-function. 

    This function registers with ARP-module to get notifications
    about the incoming packets. Checks whether the WiFi MAC is 
    connected to an Access-Point or not.

  Parameters:
	None

  Returns:
  	None
  ***************************************************************/
void ZeroconfLLInitialize(void)
{
	/* ARP is core module for IPv4 LL protocol.
	 * Register event callbacks with ARP, to get 
	 * notified. */
	arp_reg_id = ARPRegisterCallbacks(&callbacks);
	if(arp_reg_id <0)
	{
		WARN_ZCLL_PRINT("ZeroconfLLInitialize: ARP Callback registration Failed!!! \r\n");
		return;
	}
			
	/* Check for the presence of Interface 
     * Currently there's no way to check the
     * presence of interface. So always true. 
     * Later it needs to replaced by actual
     * condition */
	if(0)
	{
		zcll_state = SM_INTF_NOT_PRESENT;
		return;
	}

	if(!MACIsLinked())
	{
		zcll_state = SM_INTF_NOT_CONNECTED;
		return;
	}
	
	/* check if DHCP-Client is enabled & able to detect DHCP-Server */
	if(g_zcll_dhcp_client)
	{
		zcll_state = SM_DHCP_PRESENT;
		zcll_dhcp_substate = ZCLL_DHCP_INIT;
		return;
		
	}
	
	zcll_state = SM_ADDR_INIT;
	/* setup random number generator
	* we key this off the MAC-48 HW identifier
	* the first 3 octets are the manufacturer
	* the next 3 the serial number
	* we'll use the last four for the largest variety
	*/
	//zcll_seed_random();
			
	return;
}

/***************************************************************
  Function:
	void ZeroconfLLProcess(void)

  Summary:
	Initialization routine for Zeroconf Link-Local state-machine.
    
  Description:
    This is Polled from Main-Application & Designed to support 
    co-operative multi-tasking. This needs to retrun to Main, 
    if we have to wait for Longer durations.

    This is the main function for Zeroconf's Link-Local and takes 
    the actions accoding to current-state and event-notifications
    from ARP-Module.

  Parameters:
	None

  Returns:
  	None
  ***************************************************************/


void ZeroconfLLProcess(void)
{
	static TICK event_time; // Internal Timer, to keep track of events
	static unsigned char time_recorded; // Flag to indicate event_time is loaded
	static unsigned char defended; // Flag to indicate, whether or not defended earlier
	static TICK random_delay;

	if(!MACIsLinked())
	{
		zcll_state = SM_INTF_NOT_CONNECTED;
	}

	switch(zcll_state)
	{			
	case SM_INIT:
		WARN_ZCLL_PRINT("SM_INIT: Wrong state \r\n");
		break;

	case SM_INTF_NOT_PRESENT:
		DEBUG_ZCLL_PRINT("SM_INTF_NOT_PRESENT: Intf not detected \r\n");
		break;

	case SM_INTF_NOT_CONNECTED:

		//DEBUG_ZCLL_MESG(zeroconf_dbg_msg,"SM_INTF_NOT_CONNECTED \r\n");
		//DEBUG_ZCLL_PRINT((char*)zeroconf_dbg_msg);

		if(!MACIsLinked())
		{
			//INFO_ZCLL_PRINT((char *)("MAC is not connected yet \r\n"));
			return;
		}
		else
		{
			/* Interface is connected now */
			zcll_state = SM_DHCP_PRESENT;
			zcll_dhcp_substate = ZCLL_DHCP_INIT;
			time_recorded = 0;
			event_time = 0;
			defended = 0;
		}

	case SM_DHCP_PRESENT:
		{
			//DEBUG_ZCLL_PRINT("SM_INTF_DHCP_PRESENT \r\n");

			if(!g_zcll_dhcp_client)
			{
				zcll_state = SM_ADDR_INIT;
			}
#if defined(STACK_USE_DHCP_CLIENT)
			else
			{

				switch(zcll_dhcp_substate)
				{
				case ZCLL_DHCP_INIT:

					DEBUG_ZCLL_PRINT("ZCLL_DHCP_INIT: Entered \r\n");
					DEBUG_ZCLL_MESG((char *) zeroconf_dbg_msg,"TICKS_PER_SECOND = %ld \r\n", 
						((TICK) (TICKS_PER_SECOND)));
					DEBUG_ZCLL_PRINT((char *) zeroconf_dbg_msg);
					if(!AppConfig.Flags.bIsDHCPEnabled)
					{
						DEBUG_ZCLL_PRINT("ZCLL_DHCP_INIT: Enabling DHCP client \r\n");
						DHCPEnable((BYTE) 0); //DHCPEnable();
						time_recorded = 0; 	
					}	
					/* Start a Fisrt-phase Timer with 1 min Timeout
					* to allow DHCP-client to IP-address DHCP-ser */

					AppConfig.MyIPAddr.Val = 0;

					event_time = TickGet();
					time_recorded = 1;
					random_delay = (TICK) (ZEROCONF_LINK_LOCAL_DHCP_TIMEOUT * \
						TICK_SECOND );
					zcll_dhcp_substate = ZCLL_DHCP_PHASE_1;
					INFO_ZCLL_PRINT("Waiting for DHCP-Client to Get IP-addr from" \
						" DHCP-server..... \r\n");

					return;

				case ZCLL_DHCP_PHASE_1:

					if(time_recorded) 
					{
						if(TickGet() - event_time < random_delay)
						{
							//if(DHCPFlags.bits.bDHCPServerDetected && 
							//   DHCPFlags.bits.bIsBound)
							if (DHCPIsServerDetected((BYTE) 0) &&
								DHCPIsBound((BYTE) 0))
							{
								INFO_ZCLL_PRINT("DHCP IP-address received. No Zeroconf " \
									"Link-Local required !! \r\n");
								INFO_ZCLL_MESG(zeroconf_dbg_msg,"DHCP IP-Addr: " \
									"%d.%d.%d.%d \r\n",
									AppConfig.MyIPAddr.v[0], 
									AppConfig.MyIPAddr.v[1],
									AppConfig.MyIPAddr.v[2], 
									AppConfig.MyIPAddr.v[3]);
								INFO_ZCLL_PRINT((char *)zeroconf_dbg_msg);
								DisplayIPValue(AppConfig.MyIPAddr); // LCD Disaply

								time_recorded = 0; // Cancel Timer
								zcll_dhcp_substate = ZCLL_DHCP_PHASE_2;
								return;

							}
							return;
						}
						// First Time out. Disable DHCP & Use Link-Local
						time_recorded = 0; // Reset Timer Flag
						event_time = 0;  // Cancel Timer

						break;
					}
					else
					{
						DEBUG_ZCLL_PRINT("ERROR !! Can't Enter this DHCP " \
							"Substate without timer \r\n");
						break;
					}

				case ZCLL_DHCP_PHASE_2:

					/* Able to get an IP-address from DHCP,
					* constantly moniotor for Validity. If
					* found invalid, move back to phase-1. */

					//if(	DHCPFlags.bits.bIsBound)
					if (DHCPIsBound((BYTE) 0)) 
					{
						return;
					}
					else
					{
						if(!AppConfig.Flags.bIsDHCPEnabled)
						{
							/* Somebody else had disabled DHCP client.
							* Goto Link-Local addressing */
							DEBUG_ZCLL_PRINT("ZCLL_DHCP_PHASE_2: Externel module " \
								"disabled DHCP-Client \r\n");
							break;
						}

						temp_IP_addr.Val = 0x0;
						time_recorded = 0;
						zcll_dhcp_substate = ZCLL_DHCP_INIT;
						return;							
					}

				default:

					DEBUG_ZCLL_PRINT("ERROR !! Invalid DHCP Substate \r\n");
					break;
				}
			}

			// No break. Fall through

			// The following is commented out, to implement the behavior described in
			// RFC 3927, section 2.11.
			// In particular, IPv4LL should not "stop the DHCP client from attempting
			// to acquire a new IP address".

			#if defined(DISREGARD_RFC3927_SECTION_2_11)
			/* Disable DHCP Client, as it's not able to get an IP */
			INFO_ZCLL_PRINT("Disabling DHCP-Client. Going to use Link-Local \r\n");
			DHCPDisable((BYTE) 0);
			#endif

#else
			INFO_ZCLL_PRINT("DHCP-Client is not present. Going to use Link-Local \r\n");
#endif
			zcll_state = SM_ADDR_INIT;
			/* Not yet seeded in init routine */
			/* setup random number generator
			* we key this off the MAC-48 HW identifier
			* the first 3 octets are the manufacturer
			* the next 3 the serial number
			* we'll use the last four for the largest variety
			*/
			//zcll_seed_random();
			DEBUG0_ZCLL_MESG(zeroconf_dbg_msg,"SM_DHCP_PRESENT --> SM_ADDR_INIT \r\n");
			DEBUG0_ZCLL_PRINT((char*)zeroconf_dbg_msg);

			// No break. Fall through
		}

	case SM_ADDR_INIT:

		ZeroconfStateMachineReset(FALSE);
		conflict_count = 0;
		AppConfig.MyIPAddr.Val = 0x0;
		DisplayIPValue(AppConfig.MyIPAddr); // LCD Display

#ifdef STACK_CLIENT_MODE
		ARPInit();
#endif
		probe_count = 0;

		zcll_state = SM_ADDR_PROBE;
		INFO_ZCLL_PRINT("ADDR_INIT --> ADDR_PROBE \r\n");

		// No break. Fall through

	case SM_ADDR_PROBE:

		//DEBUG_ZCLL_PRINT("SM_ADDR_PROBE \r\n");

		switch ( zgzc_wait_for(&random_delay, &event_time, &time_recorded) )
		{
		case ZGZC_STARTED_WAITING:

			if (probe_count == 0)
			{
				// First probe. Wait for [0 ~ PROBE_WAIT] seconds before sending the probe.

				//random_delay = (TICK)(((zcll_rand()) % (PROBE_WAIT) * TICK_SECOND));
				//if (random_delay == 0) random_delay = (TICK) TICK_SECOND;

				random_delay = (TICK) (zcll_rand() % (PROBE_WAIT * TICK_SECOND));

				DEBUG0_ZCLL_MESG(zeroconf_dbg_msg,"PROBE_WAIT Random Delay [%d]: %ld secs \r\n",
					probe_count,
					random_delay);
			}
			else if (probe_count < PROBE_NUM)
			{
				// Subsequent probes. Wait for [PROBE_MIN ~ PROBE_MAX] seconds before sending the probe.

				// random_delay = (TICK) ( (((zcll_rand() % (PROBE_MAX-PROBE_MIN+1))+PROBE_MIN) * TICKS_PER_SECOND) + (TICKS_PER_SECOND>>3) );
				// Added a little bit more delay to pass conformance test.
				
				random_delay = (TICK) ( (zcll_rand() % ((PROBE_MAX-PROBE_MIN) * TICKS_PER_SECOND) ) +
					(PROBE_MIN * TICKS_PER_SECOND) );

				DEBUG0_ZCLL_MESG(zeroconf_dbg_msg,"PROBE Random Delay [%d]: %ld ticks \r\n",
					probe_count,
					random_delay);
			}
			else
			{
				// Completed PROBE_NUM of probes. Now wait for ANNOUNCE_WAIT seconds to determine if
				// we can claim it.

				random_delay = (TICK) (ANNOUNCE_WAIT * TICK_SECOND);
				DEBUG0_ZCLL_MESG(zeroconf_dbg_msg,"ANNOUNCE_WAIT delay [%d]: %ld ticks\r\n",
					probe_count,
					random_delay /*TICK_SECOND */);
			}

			DEBUG0_ZCLL_PRINT((char*)zeroconf_dbg_msg);

			// Intentional fall-through

		case ZGZC_KEEP_WAITING:

			// Not Completed the delay proposed
			return;
		}

		// Completed the delay required

		DEBUG0_ZCLL_MESG(zeroconf_dbg_msg,"   delay: %ld ticks " \
			"completed \r\n", random_delay);
		DEBUG0_ZCLL_PRINT((char *)zeroconf_dbg_msg);

		if(zcll_flags.bits.probe_conflict)
		{
			/* Conflict with selected address */
			INFO_ZCLL_PRINT("Probe Conflict-1 Detected. Need to select diff addr \r\n");
			ZeroconfStateMachineReset(FALSE);
			temp_IP_addr.Val = 0x0;

			conflict_count++;
			AppConfig.MyIPAddr.Val = 0x0;
		}
#ifdef STACK_CLIENT_MODE
		else if((conflict_count == 0) && temp_IP_addr.Val && (ARPIsResolved(&temp_IP_addr, &temp_MAC_addr)) ) 
		{
			if(!memcmp (&temp_MAC_addr, &AppConfig.MyMACAddr, 6) )
			{
				DEBUG0_ZCLL_PRINT("SM_ADDR_PROBE: Resolved with our address only. " \
					"Rare Case !!!! \r\n");
			}
			else
			{
				/* Conflict with selected address */
				INFO_ZCLL_PRINT("Probe Conflict-2 Detected. Need to select diff addr \r\n");
				ZeroconfStateMachineReset(FALSE);
				temp_IP_addr.Val = 0x0;

				conflict_count++;
				AppConfig.MyIPAddr.Val = 0x0;
			}
		}
#endif

		if ((zcll_flags.bits.probe_conflict == 1) ||
			(!bDefaultIPTried))
		{
			/*
			* Pick random IP address in IPv4 link-local range
			* 169.254.1.0/16 is the allowed address range however 
			* 169.254.0.0/24 and 169.254.255.0/24 must be excluded, 
			* which removes 512 address from our 65535 candidates. 
			* That leaves us with 65023 (0xfdff) 
			*/

			// Need to start/restart the probe procedure.
			probe_count = 0;

			if ((!bDefaultIPTried) &&
				(AppConfig.DefaultIPAddr.v[0] == 169) && 
				(AppConfig.DefaultIPAddr.v[1] == 254) &&
				(AppConfig.DefaultIPAddr.v[2] != 0) &&
				(AppConfig.DefaultIPAddr.v[2] != 255))
			{
				// First probe, and the default IP is a valid IPv4LL address.
				// Use it.

				temp_IP_addr.Val = swapl(AppConfig.DefaultIPAddr.Val);
				bDefaultIPTried = TRUE;
			}
			else
			{
				temp_IP_addr.Val = (IPV4_LLBASE | ((abs(zcll_rand()) % 0xfdff) ));
			}                

			INFO_ZCLL_MESG(zeroconf_dbg_msg,"Picked IP-Addr [%d]: %d.%d.%d.%d \r\n",
				probe_count,
				temp_IP_addr.v[3],temp_IP_addr.v[2],
				temp_IP_addr.v[1],temp_IP_addr.v[0]);
			INFO_ZCLL_PRINT((char *)zeroconf_dbg_msg);

			temp_IP_addr.Val = swapl((DWORD) temp_IP_addr.Val);
		}

		// ToDo: check the max probe limit and probing rate
		if((zcll_flags.bits.probe_conflict == 1) || (probe_count < PROBE_NUM))
		{

			zcll_flags.bits.probe_conflict = 0;
			ARPAction(AppConfig.MyIPAddr.Val, temp_IP_addr.Val, ARP_REQ,ARPProbe);
			probe_count++;

			DEBUG0_ZCLL_MESG(zeroconf_dbg_msg, "Sending ARP [%d]\r\n", probe_count);
			DEBUG0_ZCLL_PRINT((char *)zeroconf_dbg_msg);

			break;
		}

		// No conflict detected ...

		if(probe_count >= PROBE_NUM) 
		{		
			zcll_state = SM_ADDR_CLAIM;
			announce_count = 0;

			INFO_ZCLL_PRINT("ADDR_PROBE --> ADDR_CLAIM \r\n");

			return;
		}

		break;

	case SM_ADDR_CLAIM:

		switch ( zgzc_wait_for(&random_delay, &event_time, &time_recorded) )
		{
		case ZGZC_STARTED_WAITING:
			if (announce_count == 0)
			{
				// First announcement is immediate. We have passed the ANNOUNCE_WAIT in
				// PROBE state already.

				random_delay = 0;
			}
			else 
			{
				// Subsequent announcements need to wait ANNOUNCE_INTERVAL seconds
				// before sending the announcement.

				random_delay = (TICK)(ANNOUNCE_INTERVAL * TICK_SECOND);
			}
			// Intentional fall-through

		case ZGZC_KEEP_WAITING:

			// Not Completed the delay proposed
			return;
		}

		// Completed the delay required

		DEBUG0_ZCLL_MESG(zeroconf_dbg_msg,"ANNOUNCE delay: %ld ticks completed \r\n", random_delay);
		DEBUG0_ZCLL_PRINT((char *)zeroconf_dbg_msg);

		if ( announce_count < ANNOUNCE_NUM )
		{
			ARPAction(temp_IP_addr.Val,temp_IP_addr.Val,ARP_REQ,ARPClaim);
			announce_count++;

			DEBUG0_ZCLL_MESG(zeroconf_dbg_msg, "Sending ANNOUNCEMENT [%d]\r\n", announce_count);
			DEBUG0_ZCLL_PRINT((char *)zeroconf_dbg_msg);
		}
		else 
		{
			// Claim it. Goto DEFEND state

			AppConfig.MyIPAddr = temp_IP_addr;
			AppConfig.MyMask.Val = 0x0000FFFF;
			zcll_state = SM_ADDR_DEFEND;
			DisplayIPValue(AppConfig.MyIPAddr);
			INFO_ZCLL_MESG(zeroconf_dbg_msg,"\r\n******** Taken IP-Addr: " \
				"%d.%d.%d.%d ******** \r\n",
				AppConfig.MyIPAddr.v[0], AppConfig.MyIPAddr.v[1], 
				AppConfig.MyIPAddr.v[2],AppConfig.MyIPAddr.v[3]);
			INFO_ZCLL_PRINT((char *)zeroconf_dbg_msg);
			INFO_ZCLL_PRINT("ADDR_CLAIM --> ADDR_DEFEND \r\n");
		}

		break;

	case SM_ADDR_DEFEND:

		//DEBUG_ZCLL_PRINT("SM_ADDR_DEFEND \r\n");

		if( zcll_flags.bits.late_conflict)
		{
			if (!defended)
			{
				zcll_flags.bits.late_conflict = 0;
				INFO_ZCLL_PRINT("CONFLICT DETECTED !!! \r\n");

				INFO_ZCLL_PRINT("Defending the Self Address once \r\n");
				ARPAction(AppConfig.MyIPAddr.Val, AppConfig.MyIPAddr.Val,ARP_RESP,ARPDefend); 

				defended = 1;
			}
			else
			{
				// We are not allowed to defend another conflict during an active defended period

				INFO_ZCLL_PRINT("Releasing the IP-Address because of multiple Conflicts \r\n");

				zcll_state = SM_ADDR_RELEASE;

				defended = 0;
				event_time = 0;
				random_delay = 0;

				INFO_ZCLL_PRINT("ADDR_DEFEND --> ADDR_RELEASE \r\n");
				break;
			}
		}

		if (defended)
		{
			switch ( zgzc_wait_for(&random_delay, &event_time, &time_recorded) )
			{
			case ZGZC_STARTED_WAITING:

				random_delay = (TICK)(DEFEND_INTERVAL * TICK_SECOND);
				DEBUG0_ZCLL_MESG(zeroconf_dbg_msg,"DEFEND_INTERVAL Delay : %ld ticks\r\n",
					random_delay/*TICK_SECOND */);
				DEBUG0_ZCLL_PRINT((char *)zeroconf_dbg_msg);

				// Intentional fall-through

			case ZGZC_KEEP_WAITING:

				// Not Completed the delay proposed
				return;
			}

			// Completed the delay required

			DEBUG0_ZCLL_MESG(zeroconf_dbg_msg,"ANNOUNCE delay: %ld ticks " \
				"completed \r\n", random_delay);
			DEBUG0_ZCLL_PRINT((char *)zeroconf_dbg_msg);

			defended = 0;
		}

		break;

	case SM_ADDR_RELEASE:

		INFO_ZCLL_PRINT("ADDR_RELEASE --> ADDR_INIT\r\n");

		AppConfig.MyIPAddr.Val = 0x00;
		
		// Need New Addr
		temp_IP_addr.Val = (IPV4_LLBASE | ((abs(zcll_rand()) % 0xfdff) ));
		temp_IP_addr.Val = swapl((DWORD) temp_IP_addr.Val);

		zcll_state = SM_ADDR_INIT;
		time_recorded = 0;
		defended = 0;
		event_time = 0;
		break;

	default:
		break;	
	}
}		
#endif //#if defined(STACK_USE_ZERCONF_LINK_LOCAL)



