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-rw-r--r--digital/avr/modules/usb/lufa/Demos/RNDISEthernet/DHCP.c118
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diff --git a/digital/avr/modules/usb/lufa/Demos/RNDISEthernet/DHCP.c b/digital/avr/modules/usb/lufa/Demos/RNDISEthernet/DHCP.c
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+++ b/digital/avr/modules/usb/lufa/Demos/RNDISEthernet/DHCP.c
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+/*
+ LUFA Library
+ Copyright (C) Dean Camera, 2009.
+
+ dean [at] fourwalledcubicle [dot] com
+ www.fourwalledcubicle.com
+*/
+
+/*
+ Copyright 2009 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+ Permission to use, copy, modify, and distribute this software
+ and its documentation for any purpose and without fee is hereby
+ granted, 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
+ *
+ * Dynamic Host Configuration Protocol (DHCP) packet handling routines. This protocol
+ * handles the automatic IP negotiation to the host, so that the host will use the provided
+ * IP address given to it by the device.
+ */
+
+#include "DHCP.h"
+
+/** Processes a DHCP packet inside an Ethernet frame, and writes the appropriate response
+ * to the output Ethernet frame if the host is requesting or accepting an IP address.
+ *
+ * \param IPHeaderInStart Pointer to the start of the incomming packet's IP header
+ * \param DHCPHeaderInStart Pointer to the start of the incomming packet's DHCP header
+ * \param DHCPHeaderOutStart Pointer to the start of the outgoing packet's DHCP header
+ *
+ * \return The number of bytes written to the out Ethernet frame if any, NO_RESPONSE otherwise
+ */
+int16_t DHCP_ProcessDHCPPacket(void* IPHeaderInStart, void* DHCPHeaderInStart, void* DHCPHeaderOutStart)
+{
+ IP_Header_t* IPHeaderIN = (IP_Header_t*)IPHeaderInStart;
+ DHCP_Header_t* DHCPHeaderIN = (DHCP_Header_t*)DHCPHeaderInStart;
+ DHCP_Header_t* DHCPHeaderOUT = (DHCP_Header_t*)DHCPHeaderOutStart;
+
+ uint8_t* DHCPOptionsINStart = (uint8_t*)(DHCPHeaderInStart + sizeof(DHCP_Header_t));
+ uint8_t* DHCPOptionsOUTStart = (uint8_t*)(DHCPHeaderOutStart + sizeof(DHCP_Header_t));
+
+ DecodeDHCPHeader(DHCPHeaderInStart);
+
+ /* Zero out the response DHCP packet, as much of it legacy and left at 0 */
+ memset(DHCPHeaderOUT, 0, sizeof(DHCP_Header_t));
+
+ /* Fill out the response DHCP packet */
+ DHCPHeaderOUT->HardwareType = DHCPHeaderIN->HardwareType;
+ DHCPHeaderOUT->Operation = DHCP_OP_BOOTREPLY;
+ DHCPHeaderOUT->HardwareAddressLength = DHCPHeaderIN->HardwareAddressLength;
+ DHCPHeaderOUT->Hops = 0;
+ DHCPHeaderOUT->TransactionID = DHCPHeaderIN->TransactionID;
+ DHCPHeaderOUT->ElapsedSeconds = 0;
+ DHCPHeaderOUT->Flags = DHCPHeaderIN->Flags;
+ DHCPHeaderOUT->YourIP = ClientIPAddress;
+ memcpy(&DHCPHeaderOUT->ClientHardwareAddress, &DHCPHeaderIN->ClientHardwareAddress, sizeof(MAC_Address_t));
+ DHCPHeaderOUT->Cookie = SwapEndian_32(DHCP_MAGIC_COOKIE);
+
+ /* Alter the incomming IP packet header so that the corrected IP source and destinations are used - this means that
+ when the response IP header is generated, it will use the corrected addresses and not the null/broatcast addresses */
+ IPHeaderIN->SourceAddress = ClientIPAddress;
+ IPHeaderIN->DestinationAddress = ServerIPAddress;
+
+ /* Process the incomming DHCP packet options */
+ while (DHCPOptionsINStart[0] != DHCP_OPTION_END)
+ {
+ /* Find the Message Type DHCP option, to determine the type of DHCP packet */
+ if (DHCPOptionsINStart[0] == DHCP_OPTION_MESSAGETYPE)
+ {
+ if ((DHCPOptionsINStart[2] == DHCP_MESSAGETYPE_DISCOVER) || (DHCPOptionsINStart[2] == DHCP_MESSAGETYPE_REQUEST))
+ {
+ /* Fill out the response DHCP packet options for a DHCP OFFER or ACK response */
+
+ *(DHCPOptionsOUTStart++) = DHCP_OPTION_MESSAGETYPE;
+ *(DHCPOptionsOUTStart++) = 1;
+ *(DHCPOptionsOUTStart++) = (DHCPOptionsINStart[2] == DHCP_MESSAGETYPE_DISCOVER) ? DHCP_MESSAGETYPE_OFFER
+ : DHCP_MESSAGETYPE_ACK;
+
+ *(DHCPOptionsOUTStart++) = DHCP_OPTION_SUBNETMASK;
+ *(DHCPOptionsOUTStart++) = 4;
+ *(DHCPOptionsOUTStart++) = 0xFF;
+ *(DHCPOptionsOUTStart++) = 0xFF;
+ *(DHCPOptionsOUTStart++) = 0xFF;
+ *(DHCPOptionsOUTStart++) = 0x00;
+
+ *(DHCPOptionsOUTStart++) = DHCP_OPTION_DHCPSERVER;
+ *(DHCPOptionsOUTStart++) = sizeof(IP_Address_t);
+ memcpy(DHCPOptionsOUTStart, &ServerIPAddress, sizeof(IP_Address_t));
+ DHCPOptionsOUTStart += sizeof(IP_Address_t);
+
+ *(DHCPOptionsOUTStart++) = DHCP_OPTION_END;
+
+ return (sizeof(DHCP_Header_t) + 12 + sizeof(IP_Address_t));
+ }
+ }
+
+ /* Go to the next DHCP option - skip one byte if option is a padding byte, else skip the complete option's size */
+ DHCPOptionsINStart += ((DHCPOptionsINStart[0] == DHCP_OPTION_PAD) ? 1 : (DHCPOptionsINStart[1] + 2));
+ }
+
+ return NO_RESPONSE;
+}