diff options
Diffstat (limited to 'Projects/Webserver/Lib/DHCPCommon.c')
| -rw-r--r-- | Projects/Webserver/Lib/DHCPCommon.c | 103 | 
1 files changed, 103 insertions, 0 deletions
| diff --git a/Projects/Webserver/Lib/DHCPCommon.c b/Projects/Webserver/Lib/DHCPCommon.c new file mode 100644 index 0000000000..6d80f65cae --- /dev/null +++ b/Projects/Webserver/Lib/DHCPCommon.c @@ -0,0 +1,103 @@ +/* +             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 + | 
