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Diffstat (limited to 'Projects/Webserver/Lib/DHCPClientApp.c')
| -rw-r--r-- | Projects/Webserver/Lib/DHCPClientApp.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/Projects/Webserver/Lib/DHCPClientApp.c b/Projects/Webserver/Lib/DHCPClientApp.c new file mode 100644 index 0000000000..760718127e --- /dev/null +++ b/Projects/Webserver/Lib/DHCPClientApp.c @@ -0,0 +1,208 @@ +/* + 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 + * + * 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" + +#if defined(ENABLE_DHCP_CLIENT) || defined(__DOXYGEN__) + +/** 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(DHCP_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(DHCP_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 += DHCPCommon_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) && + DHCPCommon_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)); + DHCPCommon_GetOption(AppData->Options, DHCP_OPTION_SUBNET_MASK, &AppState->DHCPClient.DHCPOffer_Data.Netmask); + DHCPCommon_GetOption(AppData->Options, DHCP_OPTION_ROUTER, &AppState->DHCPClient.DHCPOffer_Data.GatewayIP); + DHCPCommon_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 += DHCPCommon_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 += DHCPCommon_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) && + DHCPCommon_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); + + 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* const 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); +} + +#endif + |