Add DHCP server to the Webserver demo for automatic network configuration. Correct uIP timer clock not tracking the correct timespan.

8 files changed, 410 insertions, 28 deletions

diff --git a/Projects/Webserver/Lib/DHCPApp.c b/Projects/Webserver/Lib/DHCPApp.c
new file mode 100644
index 000000000..ec5a815ef
--- /dev/null
+++ b/Projects/Webserver/Lib/DHCPApp.c
@@ -0,0 +1,237 @@
+/*

+             LUFA Library

+     Copyright (C) Dean Camera, 2010.

+              

+  dean [at] fourwalledcubicle [dot] com

+      www.fourwalledcubicle.com

+*/

+

+/*

+  Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)

+

+  Permission to use, copy, modify, distribute, and sell this 

+  software and its documentation for any purpose is hereby granted

+  without fee, provided that the above copyright notice appear in 

+  all copies and that both that the copyright notice and this

+  permission notice and warranty disclaimer appear in supporting 

+  documentation, and that the name of the author not be used in 

+  advertising or publicity pertaining to distribution of the 

+  software without specific, written prior permission.

+

+  The author disclaim all warranties with regard to this

+  software, including all implied warranties of merchantability

+  and fitness.  In no event shall the author be liable for any

+  special, indirect or consequential damages or any damages

+  whatsoever resulting from loss of use, data or profits, whether

+  in an action of contract, negligence or other tortious action,

+  arising out of or in connection with the use or performance of

+  this software.

+*/

+

+/** \file

+ *

+ *  DHCP Client Application. When connected to the uIP stack, this will retrieve IP configuration settings from the

+ *  DHCP server on the network.

+ */

+ 

+#include "DHCPApp.h"

+

+#if defined(ENABLE_DHCP)

+/** Timer for managing the timeout period for a DHCP server to respond */

+struct timer DHCPTimer;

+

+/** Initialization function for the DHCP client. */

+void DHCPApp_Init(void)

+{

+	uip_udp_appstate_t* const AppState = &uip_udp_conn->appstate;

+	

+	/* Create a new UDP connection to the DHCP server port for the DHCP solicitation */

+	uip_ipaddr_t DHCPServerIPAddress;

+	uip_ipaddr(&DHCPServerIPAddress, 255, 255, 255, 255);

+	AppState->Connection = uip_udp_new(&DHCPServerIPAddress, HTONS(DHCPC_SERVER_PORT));

+	

+	/* If the connection was sucessfully created, bind it to the local DHCP client port */

+	if(AppState->Connection != NULL)

+	{

+		uip_udp_bind(AppState->Connection, HTONS(DHCPC_CLIENT_PORT));

+		AppState->CurrentState = DHCP_STATE_SendDiscover;

+	}

+

+	/* Set timeout period to half a second for a DHCP server to respond */

+	timer_set(&DHCPTimer, CLOCK_SECOND / 2);

+}

+ 

+/** uIP stack application callback for the DHCP client. This function must be called each time the TCP/IP stack 

+ *  needs a UDP packet to be processed.

+ */

+void DHCPApp_Callback(void)

+{

+	uip_udp_appstate_t* const AppState    = &uip_udp_conn->appstate;

+	DHCP_Header_t*      const AppData     = (DHCP_Header_t*)uip_appdata;

+	uint16_t                  AppDataSize = 0;

+	

+	switch (AppState->CurrentState)

+	{

+		case DHCP_STATE_SendDiscover:

+			/* Clear all DHCP settings, reset client IP address */

+			memset(&AppState->DHCPOffer_Data, 0x00, sizeof(AppState->DHCPOffer_Data));

+			uip_sethostaddr(&AppState->DHCPOffer_Data.AllocatedIP);

+

+			/* Fill out the DHCP response header */

+			AppDataSize += DHCPApp_FillDHCPHeader(AppData, DHCP_DISCOVER, AppState);

+			

+			/* Add the required DHCP options list to the packet */

+			uint8_t RequiredOptionList[] = {DHCP_OPTION_SUBNET_MASK, DHCP_OPTION_ROUTER, DHCP_OPTION_DNS_SERVER};

+			AppDataSize += DHCPApp_SetOption(AppData->Options, DHCP_OPTION_REQ_LIST, sizeof(RequiredOptionList),

+			                                 RequiredOptionList);			

+			

+			/* Send the DHCP DISCOVER packet */

+			uip_send(AppData, AppDataSize);

+

+			/* Reset the timeout timer, progress to next state */

+			timer_reset(&DHCPTimer);

+			AppState->CurrentState = DHCP_STATE_WaitForResponse;			

+			

+			break;

+		case DHCP_STATE_WaitForResponse:

+			if (!(uip_newdata()))

+			{

+				/* Check if the DHCP timeout period has expired while waiting for a response */

+				if (timer_expired(&DHCPTimer))

+				  AppState->CurrentState = DHCP_STATE_SendDiscover;

+				

+				break;

+			}

+			  

+			uint8_t OfferResponse_MessageType;

+			if ((AppData->TransactionID == DHCP_TRANSACTION_ID) &&

+			    DHCPApp_GetOption(AppData->Options, DHCP_OPTION_MSG_TYPE, &OfferResponse_MessageType) &&

+			    (OfferResponse_MessageType == DHCP_OFFER))

+			{

+				/* Received a DHCP offer for an IP address, copy over values for later request */

+				memcpy(&AppState->DHCPOffer_Data.AllocatedIP, &AppData->YourIP, sizeof(uip_ipaddr_t));

+				DHCPApp_GetOption(AppData->Options, DHCP_OPTION_SUBNET_MASK, &AppState->DHCPOffer_Data.Netmask);

+				DHCPApp_GetOption(AppData->Options, DHCP_OPTION_ROUTER,      &AppState->DHCPOffer_Data.GatewayIP);

+				DHCPApp_GetOption(AppData->Options, DHCP_OPTION_SERVER_ID,   &AppState->DHCPOffer_Data.ServerIP);

+				

+				timer_reset(&DHCPTimer);

+				AppState->CurrentState = DHCP_STATE_SendRequest;

+			}

+

+			break;

+		case DHCP_STATE_SendRequest:

+			/* Fill out the DHCP response header */

+			AppDataSize += DHCPApp_FillDHCPHeader(AppData, DHCP_REQUEST, AppState);

+

+			/* Add the DHCP REQUESTED IP ADDRESS option to the packet */

+			AppDataSize += DHCPApp_SetOption(AppData->Options, DHCP_OPTION_REQ_IPADDR, sizeof(uip_ipaddr_t),

+			                                 &AppState->DHCPOffer_Data.AllocatedIP);

+

+			/* Add the DHCP SERVER IP ADDRESS option to the packet */

+			AppDataSize += DHCPApp_SetOption(AppData->Options, DHCP_OPTION_SERVER_ID, sizeof(uip_ipaddr_t),

+			                                 &AppState->DHCPOffer_Data.ServerIP);

+

+			/* Send the DHCP REQUEST packet */

+			uip_send(AppData, AppDataSize);

+			

+			/* Reset the timeout timer, progress to next state */

+			timer_reset(&DHCPTimer);

+			AppState->CurrentState = DHCP_STATE_WaitForACK;

+

+			break;

+		case DHCP_STATE_WaitForACK:

+			if (!(uip_newdata()))

+			{

+				/* Check if the DHCP timeout period has expired while waiting for a response */

+				if (timer_expired(&DHCPTimer))

+				  AppState->CurrentState = DHCP_STATE_SendDiscover;

+				

+				break;

+			}

+			

+			uint8_t RequestResponse_MessageType;

+			if ((AppData->TransactionID == DHCP_TRANSACTION_ID) &&

+			    DHCPApp_GetOption(AppData->Options, DHCP_OPTION_MSG_TYPE, &RequestResponse_MessageType) &&

+			    (RequestResponse_MessageType == DHCP_ACK))

+			{

+				/* Set the new network parameters from the DHCP server */

+				uip_sethostaddr(&AppState->DHCPOffer_Data.AllocatedIP);

+				uip_setnetmask(&AppState->DHCPOffer_Data.Netmask);

+				uip_setdraddr(&AppState->DHCPOffer_Data.GatewayIP);

+			

+				AppState->CurrentState = DHCP_STATE_AddressLeased;

+			}

+			

+			break;

+	}

+}

+

+uint16_t DHCPApp_FillDHCPHeader(DHCP_Header_t* DHCPHeader, uint8_t DHCPMessageType, uip_udp_appstate_t* AppState)

+{

+	/* Erase existing packet data so that we start will all 0x00 DHCP header data */

+ 	memset(DHCPHeader, 0, sizeof(DHCP_Header_t));

+

+	/* Fill out the DHCP packet header */

+	DHCPHeader->Operation             = DHCP_OP_BOOTREQUEST;

+	DHCPHeader->HardwareType          = DHCP_HTYPE_ETHERNET;

+	DHCPHeader->HardwareAddressLength = sizeof(MACAddress);

+	DHCPHeader->Hops                  = 0;

+	DHCPHeader->TransactionID         = DHCP_TRANSACTION_ID;

+	DHCPHeader->ElapsedSeconds        = 0;

+	DHCPHeader->Flags                 = HTONS(BOOTP_BROADCAST);

+	memcpy(&DHCPHeader->ClientIP, &uip_hostaddr, sizeof(uip_ipaddr_t));

+	memcpy(&DHCPHeader->YourIP, &AppState->DHCPOffer_Data.AllocatedIP, sizeof(uip_ipaddr_t));

+	memcpy(&DHCPHeader->NextServerIP, &AppState->DHCPOffer_Data.ServerIP, sizeof(uip_ipaddr_t));

+	memcpy(&DHCPHeader->ClientHardwareAddress, &MACAddress, sizeof(struct uip_eth_addr));

+	DHCPHeader->Cookie                = DHCP_MAGIC_COOKIE;

+	

+	/* Add a DHCP type and terminator options to the start of the DHCP options field */

+	DHCPHeader->Options[0]            = DHCP_OPTION_MSG_TYPE;

+	DHCPHeader->Options[1]            = 1;

+	DHCPHeader->Options[2]            = DHCPMessageType;

+	DHCPHeader->Options[3]            = DHCP_OPTION_END;

+	

+	/* Calculate the total number of bytes added to the outgoing packet */

+	return (sizeof(DHCP_Header_t) + 4);

+}

+

+uint8_t DHCPApp_SetOption(uint8_t* DHCPOptionList, uint8_t Option, uint8_t DataLen, void* Source)

+{

+	/* Skip through the DHCP options list until the terminator option is found */

+	while (*DHCPOptionList != DHCP_OPTION_END)

+	  DHCPOptionList += (DHCPOptionList[1] + 2);

+

+	/* Overwrite the existing terminator with the new option, add a new terminator at the end of the list */

+	DHCPOptionList[0] = Option;

+	DHCPOptionList[1] = DataLen;

+	memcpy(&DHCPOptionList[2], Source, DataLen);

+	DHCPOptionList[2 + DataLen] = DHCP_OPTION_END;

+	

+	/* Calculate the total number of bytes added to the outgoing packet */

+	return (2 + DataLen);

+}

+

+bool DHCPApp_GetOption(uint8_t* DHCPOptionList, uint8_t Option, void* Destination)

+{

+	/* Look through the incomming DHCP packet's options list for the requested option */

+	while (*DHCPOptionList != DHCP_OPTION_END)

+	{

+		/* Check if the current DHCP option in the packet is the one requested */

+		if (DHCPOptionList[0] == Option)

+		{

+			/* Copy request option's data to the destination buffer */

+			memcpy(Destination, &DHCPOptionList[2], DHCPOptionList[1]);

+			

+			/* Indicate that the requested option data was sucessfully retrieved */

+			return true;

+		}

+		

+		/* Skip to next DHCP option in the options list */

+		DHCPOptionList += (DHCPOptionList[1] + 2);

+	}

+	

+	/* Requested option not found in the incomming packet's DHCP options list */

+	return false;

+}

+

+#endif

diff --git a/Projects/Webserver/Lib/DHCPApp.h b/Projects/Webserver/Lib/DHCPApp.h
new file mode 100644
index 000000000..9e9faaa36
--- /dev/null
+++ b/Projects/Webserver/Lib/DHCPApp.h
@@ -0,0 +1,125 @@
+/*

+             LUFA Library

+     Copyright (C) Dean Camera, 2010.

+              

+  dean [at] fourwalledcubicle [dot] com

+      www.fourwalledcubicle.com

+*/

+

+/*

+  Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)

+

+  Permission to use, copy, modify, distribute, and sell this 

+  software and its documentation for any purpose is hereby granted

+  without fee, provided that the above copyright notice appear in 

+  all copies and that both that the copyright notice and this

+  permission notice and warranty disclaimer appear in supporting 

+  documentation, and that the name of the author not be used in 

+  advertising or publicity pertaining to distribution of the 

+  software without specific, written prior permission.

+

+  The author disclaim all warranties with regard to this

+  software, including all implied warranties of merchantability

+  and fitness.  In no event shall the author be liable for any

+  special, indirect or consequential damages or any damages

+  whatsoever resulting from loss of use, data or profits, whether

+  in an action of contract, negligence or other tortious action,

+  arising out of or in connection with the use or performance of

+  this software.

+*/

+

+/** \file

+ *

+ *  Header file for DHCPApp.c.

+ */

+

+#ifndef _DHCP_APP_H_

+#define _DHCP_APP_H_

+

+	/* Includes: */

+		#include <stdio.h>

+		

+		#include <uip.h>

+		

+		#include "../Webserver.h"

+		

+	/* Macros: */

+		#define DHCPC_SERVER_PORT         67

+		#define DHCPC_CLIENT_PORT         68

+

+		#define DHCP_OP_BOOTREQUEST       0x01

+		#define DHCP_OP_BOOTREPLY         0x02

+

+		#define BOOTP_BROADCAST           0x8000

+		

+		#define DHCP_MAGIC_COOKIE         0x63538263

+		

+		#define DHCP_TRANSACTION_ID       0x13245466

+

+		#define DHCP_DISCOVER             1

+		#define DHCP_OFFER                2

+		#define DHCP_REQUEST              3

+		#define DHCP_DECLINE              4

+		#define DHCP_ACK                  5

+		#define DHCP_NAK                  6

+		#define DHCP_RELEASE              7

+

+		#define DHCP_HTYPE_ETHERNET       1

+

+		#define DHCP_OPTION_SUBNET_MASK   1

+		#define DHCP_OPTION_ROUTER        3

+		#define DHCP_OPTION_DNS_SERVER    6

+		#define DHCP_OPTION_REQ_IPADDR    50

+		#define DHCP_OPTION_LEASE_TIME    51

+		#define DHCP_OPTION_MSG_TYPE      53

+		#define DHCP_OPTION_SERVER_ID     54

+		#define DHCP_OPTION_REQ_LIST      55

+		#define DHCP_OPTION_END           255

+

+	/* Type Defines: */

+		/** Type define for a DHCP packet inside an Ethernet frame. */

+		typedef struct

+		{

+			uint8_t  Operation; /**< DHCP operation, either DHCP_OP_BOOTREQUEST or DHCP_OP_BOOTREPLY */

+			uint8_t  HardwareType; /**< Hardware carrier type constant */

+			uint8_t  HardwareAddressLength;  /**< Length in bytes of a hardware (MAC) address on the network */

+			uint8_t  Hops; /**< Number of hops required to reach the server, unused */

+

+			uint32_t TransactionID; /**< Unique ID of the DHCP packet, for positive matching between sent and received packets */

+

+			uint16_t ElapsedSeconds; /**< Elapsed seconds since the request was made */

+			uint16_t Flags; /**< BOOTP packet flags */

+			

+			uip_ipaddr_t ClientIP; /**< Client IP address, if already leased an IP */

+			uip_ipaddr_t YourIP; /**< Client IP address */

+			uip_ipaddr_t NextServerIP; /**< Legacy BOOTP protocol field, unused for DHCP */

+			uip_ipaddr_t RelayAgentIP; /**< Legacy BOOTP protocol field, unused for DHCP */

+			

+			uint8_t ClientHardwareAddress[16]; /**< Hardware (MAC) address of the client making a request to the DHCP server */

+			uint8_t ServerHostnameString[64]; /**< Legacy BOOTP protocol field, unused for DHCP */

+			uint8_t BootFileName[128]; /**< Legacy BOOTP protocol field, unused for DHCP */

+			

+			uint32_t Cookie; /**< Magic BOOTP protocol cookie to indicate a valid packet */

+			

+			uint8_t  Options[]; /** DHCP message options */

+		} DHCP_Header_t;

+

+	/* Enums: */

+		enum DHCP_States_t

+		{

+			DHCP_STATE_SendDiscover,

+			DHCP_STATE_WaitForResponse,

+			DHCP_STATE_SendRequest,

+			DHCP_STATE_WaitForACK,

+			DHCP_STATE_AddressLeased,

+		};

+

+	/* Function Prototypes: */

+		void DHCPApp_Init(void);

+		void DHCPApp_Callback(void);

+		

+		uint16_t DHCPApp_FillDHCPHeader(DHCP_Header_t* DHCPHeader, uint8_t DHCPMessageType, uip_udp_appstate_t* AppState);

+		uint8_t  DHCPApp_SetOption(uint8_t* DHCPOptionList, uint8_t Option, uint8_t DataLen, void* Source);

+		bool     DHCPApp_GetOption(uint8_t* DHCPOptionList, uint8_t Option, void* Destination);

+		

+#endif

diff --git a/Projects/Webserver/Lib/WebserverApp.c b/Projects/Webserver/Lib/WebserverApp.c
index cba3b43fa..02f38be87 100644
--- a/Projects/Webserver/Lib/WebserverApp.c
+++ b/Projects/Webserver/Lib/WebserverApp.c
@@ -76,7 +76,7 @@ char PROGMEM HTTPPage[]   =
 void WebserverApp_Init(void)

 {

 	/* Listen on port 80 for HTTP connections from hosts */

-	uip_listen(HTONS(80));

+	uip_listen(HTONS(HTTP_SERVER_PORT));

 }

 

 /** uIP stack application callback for the simple HTTP webserver. This function must be called each time the

@@ -84,8 +84,9 @@ void WebserverApp_Init(void)
  */

 void WebserverApp_Callback(void)

 {

-	char*    AppDataPtr  = (char*)uip_appdata;

-	uint16_t AppDataSize = 0;

+	uip_tcp_appstate_t* const AppState    = &uip_conn->appstate;

+	char*                     AppData     = (char*)uip_appdata;

+	uint16_t                  AppDataSize = 0;

 

 	if (uip_closed() || uip_aborted() || uip_timedout())

 	{

@@ -95,12 +96,12 @@ void WebserverApp_Callback(void)
 	else if (uip_connected())

 	{

 		/* New connection - initialize connection state and data pointer to the appropriate HTTP header */

-		uip_conn->appstate.SendPos      = HTTP200Header;

-		uip_conn->appstate.CurrentState = WEBSERVER_STATE_SendHeaders;

+		AppState->SendPos      = HTTP200Header;

+		AppState->CurrentState = WEBSERVER_STATE_SendHeaders;

 	}

 

 	/* Calculate the maximum segment size and remaining data size */

-	uint16_t BytesRemaining = strlen_P(uip_conn->appstate.SendPos);

+	uint16_t BytesRemaining = strlen_P(AppState->SendPos);

 	uint16_t MaxSegSize     = uip_mss();

 

 	/* No more bytes remaining in the current data being sent - progress to next data chunk or

@@ -108,15 +109,15 @@ void WebserverApp_Callback(void)
 	if (!(BytesRemaining))

 	{

 		/* Check which data chunk we are currently sending (header or data) */

-		if (uip_conn->appstate.CurrentState == WEBSERVER_STATE_SendHeaders)

+		if (AppState->CurrentState == WEBSERVER_STATE_SendHeaders)

 		{

-			uip_conn->appstate.SendPos = HTTPPage;

-			uip_conn->appstate.CurrentState = WEBSERVER_STATE_SendData;			

+			AppState->SendPos = HTTPPage;

+			AppState->CurrentState = WEBSERVER_STATE_SendData;			

 		}

-		else if (uip_conn->appstate.CurrentState == WEBSERVER_STATE_SendData)

+		else if (AppState->CurrentState == WEBSERVER_STATE_SendData)

 		{

 			uip_close();

-			uip_conn->appstate.CurrentState = WEBSERVER_STATE_Closed;

+			AppState->CurrentState = WEBSERVER_STATE_Closed;

 		}

 		  

 		return;

@@ -133,9 +134,9 @@ void WebserverApp_Callback(void)
 	}

 

 	/* Copy over the next data segment to the application buffer, advance send position pointer */

-	strncpy_P(uip_appdata, uip_conn->appstate.SendPos, AppDataSize);

-	uip_conn->appstate.SendPos += AppDataSize;

+	strncpy_P(AppData, AppState->SendPos, AppDataSize);

+	AppState->SendPos += AppDataSize;

 

 	/* Send the data to the requesting host */

-	uip_send(AppDataPtr, AppDataSize);

+	uip_send(AppData, AppDataSize);

 }

diff --git a/Projects/Webserver/Lib/WebserverApp.h b/Projects/Webserver/Lib/WebserverApp.h
index 4d1d76cc9..3cb97c667 100644
--- a/Projects/Webserver/Lib/WebserverApp.h
+++ b/Projects/Webserver/Lib/WebserverApp.h
@@ -43,6 +43,17 @@
 		#include <LUFA/Version.h>

 		

 		#include <uip.h>

+		

+	/* Enums: */

+		enum Webserver_States_t

+		{

+			WEBSERVER_STATE_SendHeaders,

+			WEBSERVER_STATE_SendData,

+			WEBSERVER_STATE_Closed,

+		};

+	

+	/* Macros: */

+		#define HTTP_SERVER_PORT  80

 

 	/* Function Prototypes: */

 		void WebserverApp_Init(void);

diff --git a/Projects/Webserver/Lib/uip/conf/apps-conf.h b/Projects/Webserver/Lib/uip/conf/apps-conf.h
index 22bab81bf..fc9727dcd 100644
--- a/Projects/Webserver/Lib/uip/conf/apps-conf.h
+++ b/Projects/Webserver/Lib/uip/conf/apps-conf.h
@@ -1,20 +1,29 @@
 #ifndef __APPS_CONF_H__

 #define __APPS_CONF_H__

 

-	enum Webserver_States_t

-	{

-		WEBSERVER_STATE_SendHeaders,

-		WEBSERVER_STATE_SendData,

-		WEBSERVER_STATE_Closed,

-	};

-

 	typedef struct

 	{

 		uint8_t CurrentState;

 		char*   SendPos;

 	} uip_tcp_appstate_t;

 

+	typedef struct

+	{

+		uint8_t CurrentState;

+		struct  uip_udp_conn* Connection;

+		

+		struct

+		{

+			uint8_t AllocatedIP[4];

+			uint8_t Netmask[4];

+			uint8_t GatewayIP[4];

+			uint8_t ServerIP[4];

+		} DHCPOffer_Data;

+	} uip_udp_appstate_t;

+

 	#define UIP_APPCALL     WebserverApp_Callback

+	#define UIP_UDP_APPCALL DHCPApp_Callback

 	void UIP_APPCALL(void);

+	void UIP_UDP_APPCALL(void);

 

 #endif /*__APPS_CONF_H__*/

diff --git a/Projects/Webserver/Lib/uip/conf/clock-arch.c b/Projects/Webserver/Lib/uip/conf/clock-arch.c
index 8363d96e0..2007de4e9 100644
--- a/Projects/Webserver/Lib/uip/conf/clock-arch.c
+++ b/Projects/Webserver/Lib/uip/conf/clock-arch.c
@@ -21,8 +21,7 @@ ISR(TIMER1_COMPA_vect)
 void clock_init()

 {

 	OCR1A  = ((F_CPU / 1024) / 100);
-	TCCR1A = (1 << WGM12);
-	TCCR1B = ((1 << CS12) | (1 << CS10));
+	TCCR1B = ((1 << WGM12) | (1 << CS12) | (1 << CS10));
 	TIMSK1 = (1 << OCIE1A);
 }
 
diff --git a/Projects/Webserver/Lib/uip/conf/global-conf.h b/Projects/Webserver/Lib/uip/conf/global-conf.h
index a9f118d4d..5cfc60746 100644
--- a/Projects/Webserver/Lib/uip/conf/global-conf.h
+++ b/Projects/Webserver/Lib/uip/conf/global-conf.h
@@ -2,10 +2,6 @@
 #ifndef __GLOBAL_CONF_H__

 #define __GLOBAL_CONF_H__

 

-//Define frequency

-// #define F_CPU 12500000UL

-//

-

 //Include uip.h gives all the uip configurations in uip-conf.h

 #include "uip.h"

 

diff --git a/Projects/Webserver/Lib/uip/conf/uip-conf.h b/Projects/Webserver/Lib/uip/conf/uip-conf.h
index d3d9bc453..e89e7c4c6 100644
--- a/Projects/Webserver/Lib/uip/conf/uip-conf.h
+++ b/Projects/Webserver/Lib/uip/conf/uip-conf.h
@@ -79,7 +79,11 @@ typedef unsigned short uip_stats_t;
  *

  * \hideinitializer

  */

-#define UIP_CONF_UDP             0

+#if defined(ENABLE_DHCP)

+	#define UIP_CONF_UDP         1

+#else

+	#define UIP_CONF_UDP         0

+#endif

 

 /**

  * UDP checksums on or off