You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
114 lines
4.4 KiB
114 lines
4.4 KiB
/*
|
|
LUFA Library
|
|
Copyright (C) Dean Camera, 2012.
|
|
|
|
dean [at] fourwalledcubicle [dot] com
|
|
www.lufa-lib.org
|
|
*/
|
|
|
|
/*
|
|
Copyright 2012 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
|
|
*
|
|
* Internet Protocol (IP) packet handling routines. This protocol handles IP packets from the
|
|
* host which typically encapsulate other protocols such as ICMP, UDP and TCP.
|
|
*/
|
|
|
|
#include "IP.h"
|
|
|
|
/** Processes an IP packet inside an Ethernet frame, and writes the appropriate response
|
|
* to the output Ethernet frame if one is created by a sub-protocol handler.
|
|
*
|
|
* \param[in] InDataStart Pointer to the start of the incoming packet's IP header
|
|
* \param[out] OutDataStart Pointer to the start of the outgoing packet's IP header
|
|
*
|
|
* \return The number of bytes written to the out Ethernet frame if any, NO_RESPONSE if no
|
|
* response was generated, NO_PROCESS if the packet processing was deferred until the
|
|
* next Ethernet packet handler iteration
|
|
*/
|
|
int16_t IP_ProcessIPPacket(void* InDataStart,
|
|
void* OutDataStart)
|
|
{
|
|
DecodeIPHeader(InDataStart);
|
|
|
|
IP_Header_t* IPHeaderIN = (IP_Header_t*)InDataStart;
|
|
IP_Header_t* IPHeaderOUT = (IP_Header_t*)OutDataStart;
|
|
|
|
/* Header length is specified in number of longs in the packet header, convert to bytes */
|
|
uint16_t HeaderLengthBytes = (IPHeaderIN->HeaderLength * sizeof(uint32_t));
|
|
|
|
int16_t RetSize = NO_RESPONSE;
|
|
|
|
/* Check to ensure the IP packet is addressed to the virtual webserver's IP or the broadcast IP address */
|
|
if (!(IP_COMPARE(&IPHeaderIN->DestinationAddress, &ServerIPAddress)) &&
|
|
!(IP_COMPARE(&IPHeaderIN->DestinationAddress, &BroadcastIPAddress)))
|
|
{
|
|
return NO_RESPONSE;
|
|
}
|
|
|
|
/* Pass off the IP payload to the appropriate protocol processing routine */
|
|
switch (IPHeaderIN->Protocol)
|
|
{
|
|
case PROTOCOL_ICMP:
|
|
RetSize = ICMP_ProcessICMPPacket(&((uint8_t*)InDataStart)[HeaderLengthBytes],
|
|
&((uint8_t*)OutDataStart)[sizeof(IP_Header_t)]);
|
|
break;
|
|
case PROTOCOL_TCP:
|
|
RetSize = TCP_ProcessTCPPacket(InDataStart,
|
|
&((uint8_t*)InDataStart)[HeaderLengthBytes],
|
|
&((uint8_t*)OutDataStart)[sizeof(IP_Header_t)]);
|
|
break;
|
|
case PROTOCOL_UDP:
|
|
RetSize = UDP_ProcessUDPPacket(InDataStart,
|
|
&((uint8_t*)InDataStart)[HeaderLengthBytes],
|
|
&((uint8_t*)OutDataStart)[sizeof(IP_Header_t)]);
|
|
break;
|
|
}
|
|
|
|
/* Check to see if the protocol processing routine has filled out a response */
|
|
if (RetSize > 0)
|
|
{
|
|
/* Fill out the response IP packet header */
|
|
IPHeaderOUT->TotalLength = SwapEndian_16(sizeof(IP_Header_t) + RetSize);
|
|
IPHeaderOUT->TypeOfService = 0;
|
|
IPHeaderOUT->HeaderLength = (sizeof(IP_Header_t) / sizeof(uint32_t));
|
|
IPHeaderOUT->Version = 4;
|
|
IPHeaderOUT->Flags = 0;
|
|
IPHeaderOUT->FragmentOffset = 0;
|
|
IPHeaderOUT->Identification = 0;
|
|
IPHeaderOUT->HeaderChecksum = 0;
|
|
IPHeaderOUT->Protocol = IPHeaderIN->Protocol;
|
|
IPHeaderOUT->TTL = DEFAULT_TTL;
|
|
IPHeaderOUT->SourceAddress = IPHeaderIN->DestinationAddress;
|
|
IPHeaderOUT->DestinationAddress = IPHeaderIN->SourceAddress;
|
|
|
|
IPHeaderOUT->HeaderChecksum = Ethernet_Checksum16(IPHeaderOUT, sizeof(IP_Header_t));
|
|
|
|
/* Return the size of the response so far */
|
|
return (sizeof(IP_Header_t) + RetSize);
|
|
}
|
|
|
|
return RetSize;
|
|
}
|
|
|