1 files changed, 87 insertions, 0 deletions
diff --git a/Demos/Device/LowLevel/RNDISEthernet/Lib/ARP.c b/Demos/Device/LowLevel/RNDISEthernet/Lib/ARP.c
new file mode 100644
index 0000000000..24008705c1
--- /dev/null
+++ b/Demos/Device/LowLevel/RNDISEthernet/Lib/ARP.c
@@ -0,0 +1,87 @@
+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2017.
+
+  dean [at] fourwalledcubicle [dot] com
+           www.lufa-lib.org
+*/
+
+/*
+  Copyright 2017  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 disclaims 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
+ *
+ *  Address Resolution Protocol (ARP) packet handling routines. This protocol handles the
+ *  conversion of physical MAC addresses to protocol IP addresses between the host and the
+ *  device.
+ */
+
+#include "ARP.h"
+
+/** Processes an ARP packet inside an Ethernet frame, and writes the appropriate response
+ *  to the output Ethernet frame if the host is requesting the IP or MAC address of the
+ *  virtual server device on the network.
+ *
+ *  \param[in] InDataStart    Pointer to the start of the incoming packet's ARP header
+ *  \param[out] OutDataStart  Pointer to the start of the outgoing packet's ARP header
+ *
+ *  \return The number of bytes written to the out Ethernet frame if any, NO_RESPONSE otherwise
+ */
+int16_t ARP_ProcessARPPacket(void* InDataStart,
+                             void* OutDataStart)
+{
+	DecodeARPHeader(InDataStart);
+
+	ARP_Header_t* ARPHeaderIN  = (ARP_Header_t*)InDataStart;
+	ARP_Header_t* ARPHeaderOUT = (ARP_Header_t*)OutDataStart;
+
+	/* Ensure that the ARP request is a IPv4 request packet */
+	if ((SwapEndian_16(ARPHeaderIN->ProtocolType) == ETHERTYPE_IPV4) &&
+	    (SwapEndian_16(ARPHeaderIN->Operation) == ARP_OPERATION_REQUEST))
+	{
+		/* If the ARP packet is requesting the MAC or IP of the virtual webserver, return the response */
+		if (IP_COMPARE(&ARPHeaderIN->TPA, &ServerIPAddress) ||
+		    MAC_COMPARE(&ARPHeaderIN->THA, &ServerMACAddress))
+		{
+			/* Fill out the ARP response header */
+			ARPHeaderOUT->HardwareType = ARPHeaderIN->HardwareType;
+			ARPHeaderOUT->ProtocolType = ARPHeaderIN->ProtocolType;
+			ARPHeaderOUT->HLEN         = ARPHeaderIN->HLEN;
+			ARPHeaderOUT->PLEN         = ARPHeaderIN->PLEN;
+			ARPHeaderOUT->Operation    = SwapEndian_16(ARP_OPERATION_REPLY);
+
+			/* Copy over the sender MAC/IP to the target fields for the response */
+			ARPHeaderOUT->THA = ARPHeaderIN->SHA;
+			ARPHeaderOUT->TPA = ARPHeaderIN->SPA;
+
+			/* Copy over the new sender MAC/IP - MAC and IP addresses of the virtual webserver */
+			ARPHeaderOUT->SHA = ServerMACAddress;
+			ARPHeaderOUT->SPA = ServerIPAddress;
+
+			/* Return the size of the response so far */
+			return sizeof(ARP_Header_t);
+		}
+	}
+
+	return NO_RESPONSE;
+}
+