diff options
Diffstat (limited to 'Projects/Webserver/Lib/DHCPClientApp.c')
-rw-r--r-- | Projects/Webserver/Lib/DHCPClientApp.c | 528 |
1 files changed, 264 insertions, 264 deletions
diff --git a/Projects/Webserver/Lib/DHCPClientApp.c b/Projects/Webserver/Lib/DHCPClientApp.c index 9d085a785..7f822538e 100644 --- a/Projects/Webserver/Lib/DHCPClientApp.c +++ b/Projects/Webserver/Lib/DHCPClientApp.c @@ -1,264 +1,264 @@ -/*
- LUFA Library
- Copyright (C) Dean Camera, 2010.
-
- dean [at] fourwalledcubicle [dot] com
- www.fourwalledcubicle.com
-*/
-
-/*
- Copyright 2010 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.
-*/
-
-#if defined(ENABLE_DHCP_CLIENT) || defined(__DOXYGEN__)
-
-/** \file
- *
- * DHCP Client Application. When connected to the uIP stack, this will retrieve IP configuration settings from the
- * DHCP server on the network.
- */
-
-#define INCLUDE_FROM_DHCPCLIENTAPP_C
-#include "DHCPClientApp.h"
-
-/** Initialization function for the DHCP client. */
-void DHCPClientApp_Init(void)
-{
- /* Create a new UDP connection to the DHCP server port for the DHCP solicitation */
- struct uip_udp_conn* Connection = uip_udp_new(&uip_broadcast_addr, HTONS(DHCPC_SERVER_PORT));
-
- /* If the connection was successfully created, bind it to the local DHCP client port */
- if (Connection != NULL)
- {
- uip_udp_appstate_t* const AppState = &Connection->appstate;
- uip_udp_bind(Connection, HTONS(DHCPC_CLIENT_PORT));
-
- /* Set the initial client state */
- AppState->DHCPClient.CurrentState = DHCP_STATE_SendDiscover;
-
- /* Set timeout period to half a second for a DHCP server to respond */
- timer_set(&AppState->DHCPClient.Timeout, CLOCK_SECOND / 2);
- }
-}
-
-/** uIP stack application callback for the DHCP client. This function must be called each time the TCP/IP stack
- * needs a UDP packet to be processed.
- */
-void DHCPClientApp_Callback(void)
-{
- uip_udp_appstate_t* const AppState = &uip_udp_conn->appstate;
- DHCP_Header_t* const AppData = (DHCP_Header_t*)uip_appdata;
- uint16_t AppDataSize = 0;
-
- switch (AppState->DHCPClient.CurrentState)
- {
- case DHCP_STATE_SendDiscover:
- /* Clear all DHCP settings, reset client IP address */
- memset(&AppState->DHCPClient.DHCPOffer_Data, 0x00, sizeof(AppState->DHCPClient.DHCPOffer_Data));
- uip_sethostaddr((uip_ipaddr_t*)&AppState->DHCPClient.DHCPOffer_Data.AllocatedIP);
-
- /* Fill out the DHCP response header */
- AppDataSize += DHCPClientApp_FillDHCPHeader(AppData, DHCP_DISCOVER, AppState);
-
- /* Add the required DHCP options list to the packet */
- uint8_t RequiredOptionList[] = {DHCP_OPTION_SUBNET_MASK, DHCP_OPTION_ROUTER, DHCP_OPTION_DNS_SERVER};
- AppDataSize += DHCPClientApp_SetOption(AppData->Options, DHCP_OPTION_REQ_LIST, sizeof(RequiredOptionList),
- RequiredOptionList);
-
- /* Send the DHCP DISCOVER packet */
- uip_udp_send(AppDataSize);
-
- /* Reset the timeout timer, progress to next state */
- timer_reset(&AppState->DHCPClient.Timeout);
- AppState->DHCPClient.CurrentState = DHCP_STATE_WaitForOffer;
-
- break;
- case DHCP_STATE_WaitForOffer:
- if (!(uip_newdata()))
- {
- /* Check if the DHCP timeout period has expired while waiting for a response */
- if (timer_expired(&AppState->DHCPClient.Timeout))
- AppState->DHCPClient.CurrentState = DHCP_STATE_SendDiscover;
-
- break;
- }
-
- uint8_t OfferResponse_MessageType;
- if ((AppData->TransactionID == DHCP_TRANSACTION_ID) &&
- DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_MSG_TYPE, &OfferResponse_MessageType) &&
- (OfferResponse_MessageType == DHCP_OFFER))
- {
- /* Received a DHCP offer for an IP address, copy over values for later request */
- memcpy(&AppState->DHCPClient.DHCPOffer_Data.AllocatedIP, &AppData->YourIP, sizeof(uip_ipaddr_t));
- DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_SUBNET_MASK, &AppState->DHCPClient.DHCPOffer_Data.Netmask);
- DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_ROUTER, &AppState->DHCPClient.DHCPOffer_Data.GatewayIP);
- DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_SERVER_ID, &AppState->DHCPClient.DHCPOffer_Data.ServerIP);
-
- timer_reset(&AppState->DHCPClient.Timeout);
- AppState->DHCPClient.CurrentState = DHCP_STATE_SendRequest;
- }
-
- break;
- case DHCP_STATE_SendRequest:
- /* Fill out the DHCP response header */
- AppDataSize += DHCPClientApp_FillDHCPHeader(AppData, DHCP_REQUEST, AppState);
-
- /* Add the DHCP REQUESTED IP ADDRESS option to the packet */
- AppDataSize += DHCPClientApp_SetOption(AppData->Options, DHCP_OPTION_REQ_IPADDR, sizeof(uip_ipaddr_t),
- &AppState->DHCPClient.DHCPOffer_Data.AllocatedIP);
-
- /* Add the DHCP SERVER IP ADDRESS option to the packet */
- AppDataSize += DHCPClientApp_SetOption(AppData->Options, DHCP_OPTION_SERVER_ID, sizeof(uip_ipaddr_t),
- &AppState->DHCPClient.DHCPOffer_Data.ServerIP);
-
- /* Send the DHCP REQUEST packet */
- uip_udp_send(AppDataSize);
-
- /* Reset the timeout timer, progress to next state */
- timer_reset(&AppState->DHCPClient.Timeout);
- AppState->DHCPClient.CurrentState = DHCP_STATE_WaitForACK;
-
- break;
- case DHCP_STATE_WaitForACK:
- if (!(uip_newdata()))
- {
- /* Check if the DHCP timeout period has expired while waiting for a response */
- if (timer_expired(&AppState->DHCPClient.Timeout))
- AppState->DHCPClient.CurrentState = DHCP_STATE_SendDiscover;
-
- break;
- }
-
- uint8_t RequestResponse_MessageType;
- if ((AppData->TransactionID == DHCP_TRANSACTION_ID) &&
- DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_MSG_TYPE, &RequestResponse_MessageType) &&
- (RequestResponse_MessageType == DHCP_ACK))
- {
- /* Set the new network parameters from the DHCP server */
- uip_sethostaddr((uip_ipaddr_t*)&AppState->DHCPClient.DHCPOffer_Data.AllocatedIP);
- uip_setnetmask((uip_ipaddr_t*)&AppState->DHCPClient.DHCPOffer_Data.Netmask);
- uip_setdraddr((uip_ipaddr_t*)&AppState->DHCPClient.DHCPOffer_Data.GatewayIP);
-
- /* Indicate to the user that we now have a valid IP configuration */
- HaveIPConfiguration = true;
-
- AppState->DHCPClient.CurrentState = DHCP_STATE_AddressLeased;
- }
-
- break;
- }
-}
-
-/** Fills the DHCP packet response with the appropriate BOOTP header for DHCP. This fills out all the required
- * fields, leaving only the additional DHCP options to be added to the packet before it is sent to the DHCP server.
- *
- * \param[out] DHCPHeader Location in the packet buffer where the BOOTP header should be written to
- * \param[in] DHCPMessageType DHCP Message type, such as DHCP_DISCOVER
- * \param[in] AppState Application state of the current UDP connection
- *
- * \return Size in bytes of the created DHCP packet
- */
-static uint16_t DHCPClientApp_FillDHCPHeader(DHCP_Header_t* const DHCPHeader, const uint8_t DHCPMessageType, uip_udp_appstate_t* AppState)
-{
- /* Erase existing packet data so that we start will all 0x00 DHCP header data */
- memset(DHCPHeader, 0, sizeof(DHCP_Header_t));
-
- /* Fill out the DHCP packet header */
- DHCPHeader->Operation = DHCP_OP_BOOTREQUEST;
- DHCPHeader->HardwareType = DHCP_HTYPE_ETHERNET;
- DHCPHeader->HardwareAddressLength = sizeof(MACAddress);
- DHCPHeader->Hops = 0;
- DHCPHeader->TransactionID = DHCP_TRANSACTION_ID;
- DHCPHeader->ElapsedSeconds = 0;
- DHCPHeader->Flags = HTONS(BOOTP_BROADCAST);
- memcpy(&DHCPHeader->ClientIP, &uip_hostaddr, sizeof(uip_ipaddr_t));
- memcpy(&DHCPHeader->YourIP, &AppState->DHCPClient.DHCPOffer_Data.AllocatedIP, sizeof(uip_ipaddr_t));
- memcpy(&DHCPHeader->NextServerIP, &AppState->DHCPClient.DHCPOffer_Data.ServerIP, sizeof(uip_ipaddr_t));
- memcpy(&DHCPHeader->ClientHardwareAddress, &MACAddress, sizeof(struct uip_eth_addr));
- DHCPHeader->Cookie = DHCP_MAGIC_COOKIE;
-
- /* Add a DHCP message type and terminator options to the start of the DHCP options field */
- DHCPHeader->Options[0] = DHCP_OPTION_MSG_TYPE;
- DHCPHeader->Options[1] = 1;
- DHCPHeader->Options[2] = DHCPMessageType;
- DHCPHeader->Options[3] = DHCP_OPTION_END;
-
- /* Calculate the total number of bytes added to the outgoing packet */
- return (sizeof(DHCP_Header_t) + 4);
-}
-
-/** 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
- */
-static uint8_t DHCPClientApp_SetOption(uint8_t* DHCPOptionList, uint8_t Option, uint8_t DataLen, void* 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 true if the option was found in the DHCP packet's options list, false otherwise
- */
-static bool DHCPClientApp_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
+/* + LUFA Library + Copyright (C) Dean Camera, 2010. + + dean [at] fourwalledcubicle [dot] com + www.fourwalledcubicle.com +*/ + +/* + Copyright 2010 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. +*/ + +#if defined(ENABLE_DHCP_CLIENT) || defined(__DOXYGEN__) + +/** \file + * + * DHCP Client Application. When connected to the uIP stack, this will retrieve IP configuration settings from the + * DHCP server on the network. + */ + +#define INCLUDE_FROM_DHCPCLIENTAPP_C +#include "DHCPClientApp.h" + +/** Initialization function for the DHCP client. */ +void DHCPClientApp_Init(void) +{ + /* Create a new UDP connection to the DHCP server port for the DHCP solicitation */ + struct uip_udp_conn* Connection = uip_udp_new(&uip_broadcast_addr, HTONS(DHCPC_SERVER_PORT)); + + /* If the connection was successfully created, bind it to the local DHCP client port */ + if (Connection != NULL) + { + uip_udp_appstate_t* const AppState = &Connection->appstate; + uip_udp_bind(Connection, HTONS(DHCPC_CLIENT_PORT)); + + /* Set the initial client state */ + AppState->DHCPClient.CurrentState = DHCP_STATE_SendDiscover; + + /* Set timeout period to half a second for a DHCP server to respond */ + timer_set(&AppState->DHCPClient.Timeout, CLOCK_SECOND / 2); + } +} + +/** uIP stack application callback for the DHCP client. This function must be called each time the TCP/IP stack + * needs a UDP packet to be processed. + */ +void DHCPClientApp_Callback(void) +{ + uip_udp_appstate_t* const AppState = &uip_udp_conn->appstate; + DHCP_Header_t* const AppData = (DHCP_Header_t*)uip_appdata; + uint16_t AppDataSize = 0; + + switch (AppState->DHCPClient.CurrentState) + { + case DHCP_STATE_SendDiscover: + /* Clear all DHCP settings, reset client IP address */ + memset(&AppState->DHCPClient.DHCPOffer_Data, 0x00, sizeof(AppState->DHCPClient.DHCPOffer_Data)); + uip_sethostaddr((uip_ipaddr_t*)&AppState->DHCPClient.DHCPOffer_Data.AllocatedIP); + + /* Fill out the DHCP response header */ + AppDataSize += DHCPClientApp_FillDHCPHeader(AppData, DHCP_DISCOVER, AppState); + + /* Add the required DHCP options list to the packet */ + uint8_t RequiredOptionList[] = {DHCP_OPTION_SUBNET_MASK, DHCP_OPTION_ROUTER, DHCP_OPTION_DNS_SERVER}; + AppDataSize += DHCPClientApp_SetOption(AppData->Options, DHCP_OPTION_REQ_LIST, sizeof(RequiredOptionList), + RequiredOptionList); + + /* Send the DHCP DISCOVER packet */ + uip_udp_send(AppDataSize); + + /* Reset the timeout timer, progress to next state */ + timer_reset(&AppState->DHCPClient.Timeout); + AppState->DHCPClient.CurrentState = DHCP_STATE_WaitForOffer; + + break; + case DHCP_STATE_WaitForOffer: + if (!(uip_newdata())) + { + /* Check if the DHCP timeout period has expired while waiting for a response */ + if (timer_expired(&AppState->DHCPClient.Timeout)) + AppState->DHCPClient.CurrentState = DHCP_STATE_SendDiscover; + + break; + } + + uint8_t OfferResponse_MessageType; + if ((AppData->TransactionID == DHCP_TRANSACTION_ID) && + DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_MSG_TYPE, &OfferResponse_MessageType) && + (OfferResponse_MessageType == DHCP_OFFER)) + { + /* Received a DHCP offer for an IP address, copy over values for later request */ + memcpy(&AppState->DHCPClient.DHCPOffer_Data.AllocatedIP, &AppData->YourIP, sizeof(uip_ipaddr_t)); + DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_SUBNET_MASK, &AppState->DHCPClient.DHCPOffer_Data.Netmask); + DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_ROUTER, &AppState->DHCPClient.DHCPOffer_Data.GatewayIP); + DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_SERVER_ID, &AppState->DHCPClient.DHCPOffer_Data.ServerIP); + + timer_reset(&AppState->DHCPClient.Timeout); + AppState->DHCPClient.CurrentState = DHCP_STATE_SendRequest; + } + + break; + case DHCP_STATE_SendRequest: + /* Fill out the DHCP response header */ + AppDataSize += DHCPClientApp_FillDHCPHeader(AppData, DHCP_REQUEST, AppState); + + /* Add the DHCP REQUESTED IP ADDRESS option to the packet */ + AppDataSize += DHCPClientApp_SetOption(AppData->Options, DHCP_OPTION_REQ_IPADDR, sizeof(uip_ipaddr_t), + &AppState->DHCPClient.DHCPOffer_Data.AllocatedIP); + + /* Add the DHCP SERVER IP ADDRESS option to the packet */ + AppDataSize += DHCPClientApp_SetOption(AppData->Options, DHCP_OPTION_SERVER_ID, sizeof(uip_ipaddr_t), + &AppState->DHCPClient.DHCPOffer_Data.ServerIP); + + /* Send the DHCP REQUEST packet */ + uip_udp_send(AppDataSize); + + /* Reset the timeout timer, progress to next state */ + timer_reset(&AppState->DHCPClient.Timeout); + AppState->DHCPClient.CurrentState = DHCP_STATE_WaitForACK; + + break; + case DHCP_STATE_WaitForACK: + if (!(uip_newdata())) + { + /* Check if the DHCP timeout period has expired while waiting for a response */ + if (timer_expired(&AppState->DHCPClient.Timeout)) + AppState->DHCPClient.CurrentState = DHCP_STATE_SendDiscover; + + break; + } + + uint8_t RequestResponse_MessageType; + if ((AppData->TransactionID == DHCP_TRANSACTION_ID) && + DHCPClientApp_GetOption(AppData->Options, DHCP_OPTION_MSG_TYPE, &RequestResponse_MessageType) && + (RequestResponse_MessageType == DHCP_ACK)) + { + /* Set the new network parameters from the DHCP server */ + uip_sethostaddr((uip_ipaddr_t*)&AppState->DHCPClient.DHCPOffer_Data.AllocatedIP); + uip_setnetmask((uip_ipaddr_t*)&AppState->DHCPClient.DHCPOffer_Data.Netmask); + uip_setdraddr((uip_ipaddr_t*)&AppState->DHCPClient.DHCPOffer_Data.GatewayIP); + + /* Indicate to the user that we now have a valid IP configuration */ + HaveIPConfiguration = true; + + AppState->DHCPClient.CurrentState = DHCP_STATE_AddressLeased; + } + + break; + } +} + +/** Fills the DHCP packet response with the appropriate BOOTP header for DHCP. This fills out all the required + * fields, leaving only the additional DHCP options to be added to the packet before it is sent to the DHCP server. + * + * \param[out] DHCPHeader Location in the packet buffer where the BOOTP header should be written to + * \param[in] DHCPMessageType DHCP Message type, such as DHCP_DISCOVER + * \param[in] AppState Application state of the current UDP connection + * + * \return Size in bytes of the created DHCP packet + */ +static uint16_t DHCPClientApp_FillDHCPHeader(DHCP_Header_t* const DHCPHeader, const uint8_t DHCPMessageType, uip_udp_appstate_t* AppState) +{ + /* Erase existing packet data so that we start will all 0x00 DHCP header data */ + memset(DHCPHeader, 0, sizeof(DHCP_Header_t)); + + /* Fill out the DHCP packet header */ + DHCPHeader->Operation = DHCP_OP_BOOTREQUEST; + DHCPHeader->HardwareType = DHCP_HTYPE_ETHERNET; + DHCPHeader->HardwareAddressLength = sizeof(MACAddress); + DHCPHeader->Hops = 0; + DHCPHeader->TransactionID = DHCP_TRANSACTION_ID; + DHCPHeader->ElapsedSeconds = 0; + DHCPHeader->Flags = HTONS(BOOTP_BROADCAST); + memcpy(&DHCPHeader->ClientIP, &uip_hostaddr, sizeof(uip_ipaddr_t)); + memcpy(&DHCPHeader->YourIP, &AppState->DHCPClient.DHCPOffer_Data.AllocatedIP, sizeof(uip_ipaddr_t)); + memcpy(&DHCPHeader->NextServerIP, &AppState->DHCPClient.DHCPOffer_Data.ServerIP, sizeof(uip_ipaddr_t)); + memcpy(&DHCPHeader->ClientHardwareAddress, &MACAddress, sizeof(struct uip_eth_addr)); + DHCPHeader->Cookie = DHCP_MAGIC_COOKIE; + + /* Add a DHCP message type and terminator options to the start of the DHCP options field */ + DHCPHeader->Options[0] = DHCP_OPTION_MSG_TYPE; + DHCPHeader->Options[1] = 1; + DHCPHeader->Options[2] = DHCPMessageType; + DHCPHeader->Options[3] = DHCP_OPTION_END; + + /* Calculate the total number of bytes added to the outgoing packet */ + return (sizeof(DHCP_Header_t) + 4); +} + +/** 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 + */ +static uint8_t DHCPClientApp_SetOption(uint8_t* DHCPOptionList, uint8_t Option, uint8_t DataLen, void* 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 true if the option was found in the DHCP packet's options list, false otherwise + */ +static bool DHCPClientApp_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 |