forked from mfulz_github/qmk_firmware
82 lines
3.0 KiB
C
82 lines
3.0 KiB
C
/*
|
|
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
|
|
*
|
|
* Internet Control Message Protocol (ICMP) packet handling routines. This protocol handles
|
|
* Echo requests from the host, to indicate a successful network connection between the host
|
|
* and the virtual server.
|
|
*/
|
|
|
|
#include "ICMP.h"
|
|
|
|
/** Processes an ICMP packet inside an Ethernet frame, and writes the appropriate response
|
|
* to the output Ethernet frame if the host is issuing a ICMP ECHO request.
|
|
*
|
|
* \param[in] InDataStart Pointer to the start of the incoming packet's ICMP header
|
|
* \param[out] OutDataStart Pointer to the start of the outgoing packet's ICMP header
|
|
*
|
|
* \return The number of bytes written to the out Ethernet frame if any, NO_RESPONSE otherwise
|
|
*/
|
|
int16_t ICMP_ProcessICMPPacket(void* InDataStart,
|
|
void* OutDataStart)
|
|
{
|
|
ICMP_Header_t* ICMPHeaderIN = (ICMP_Header_t*)InDataStart;
|
|
ICMP_Header_t* ICMPHeaderOUT = (ICMP_Header_t*)OutDataStart;
|
|
|
|
DecodeICMPHeader(InDataStart);
|
|
|
|
/* Determine if the ICMP packet is an echo request (ping) */
|
|
if (ICMPHeaderIN->Type == ICMP_TYPE_ECHOREQUEST)
|
|
{
|
|
/* Fill out the ICMP response packet */
|
|
ICMPHeaderOUT->Type = ICMP_TYPE_ECHOREPLY;
|
|
ICMPHeaderOUT->Code = 0;
|
|
ICMPHeaderOUT->Checksum = 0;
|
|
ICMPHeaderOUT->Id = ICMPHeaderIN->Id;
|
|
ICMPHeaderOUT->Sequence = ICMPHeaderIN->Sequence;
|
|
|
|
intptr_t DataSize = FrameIN.FrameLength - ((((intptr_t)InDataStart + sizeof(ICMP_Header_t)) - (intptr_t)FrameIN.FrameData));
|
|
|
|
/* Copy the remaining payload to the response - echo requests should echo back any sent data */
|
|
memmove(&((uint8_t*)OutDataStart)[sizeof(ICMP_Header_t)],
|
|
&((uint8_t*)InDataStart)[sizeof(ICMP_Header_t)],
|
|
DataSize);
|
|
|
|
ICMPHeaderOUT->Checksum = Ethernet_Checksum16(ICMPHeaderOUT, (DataSize + sizeof(ICMP_Header_t)));
|
|
|
|
/* Return the size of the response so far */
|
|
return (DataSize + sizeof(ICMP_Header_t));
|
|
}
|
|
|
|
return NO_RESPONSE;
|
|
}
|
|
|