103 lines
3.9 KiB
C
103 lines
3.9 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
|
|
*
|
|
* Common DHCP routines to manage DHCP packet data.
|
|
*/
|
|
|
|
#include "DHCPCommon.h"
|
|
|
|
#if defined(ENABLE_DHCP_CLIENT) || defined(ENABLE_DHCP_SERVER) || defined(__DOXYGEN__)
|
|
|
|
/** Sets the given DHCP option in the DHCP packet's option list. This automatically moves the
|
|
* end of options terminator past the new option in the options list.
|
|
*
|
|
* \param[in,out] DHCPOptionList Pointer to the start of the DHCP packet's options list
|
|
* \param[in] Option DHCP option to add to the list
|
|
* \param[in] DataLen Size in bytes of the option data to add
|
|
* \param[in] OptionData Buffer where the option's data is to be sourced from
|
|
*
|
|
* \return Number of bytes added to the DHCP packet
|
|
*/
|
|
uint8_t DHCPCommon_SetOption(uint8_t* DHCPOptionList,
|
|
const uint8_t Option,
|
|
const uint8_t DataLen,
|
|
void* const OptionData)
|
|
{
|
|
/* 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], OptionData, DataLen);
|
|
DHCPOptionList[2 + DataLen] = DHCP_OPTION_END;
|
|
|
|
/* Calculate the total number of bytes added to the outgoing packet */
|
|
return (2 + DataLen);
|
|
}
|
|
|
|
/** Retrieves the given option's data (if present) from the DHCP packet's options list.
|
|
*
|
|
* \param[in,out] DHCPOptionList Pointer to the start of the DHCP packet's options list
|
|
* \param[in] Option DHCP option to retrieve to the list
|
|
* \param[out] Destination Buffer where the option's data is to be written to if found
|
|
*
|
|
* \return Boolean \c true if the option was found in the DHCP packet's options list, \c false otherwise
|
|
*/
|
|
bool DHCPCommon_GetOption(const uint8_t* DHCPOptionList,
|
|
const uint8_t Option,
|
|
void* const Destination)
|
|
{
|
|
/* Look through the incoming 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 successfully retrieved */
|
|
return true;
|
|
}
|
|
|
|
/* Skip to next DHCP option in the options list */
|
|
DHCPOptionList += (DHCPOptionList[1] + 2);
|
|
}
|
|
|
|
/* Requested option not found in the incoming packet's DHCP options list */
|
|
return false;
|
|
}
|
|
|
|
#endif
|
|
|