+/*\r
+ LUFA Library\r
+ Copyright (C) Dean Camera, 2011.\r
+\r
+ dean [at] fourwalledcubicle [dot] com\r
+ www.lufa-lib.org\r
+*/\r
+\r
+/*\r
+ Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com)\r
+\r
+ Permission to use, copy, modify, distribute, and sell this\r
+ software and its documentation for any purpose is hereby granted\r
+ without fee, provided that the above copyright notice appear in\r
+ all copies and that both that the copyright notice and this\r
+ permission notice and warranty disclaimer appear in supporting\r
+ documentation, and that the name of the author not be used in\r
+ advertising or publicity pertaining to distribution of the\r
+ software without specific, written prior permission.\r
+\r
+ The author disclaim all warranties with regard to this\r
+ software, including all implied warranties of merchantability\r
+ and fitness. In no event shall the author be liable for any\r
+ special, indirect or consequential damages or any damages\r
+ whatsoever resulting from loss of use, data or profits, whether\r
+ in an action of contract, negligence or other tortious action,\r
+ arising out of or in connection with the use or performance of\r
+ this software.\r
+*/\r
+\r
+#if defined(ENABLE_DHCP_SERVER) || defined(__DOXYGEN__)\r
+\r
+/** \file\r
+ *\r
+ * DHCP Server Application. When connected to the uIP stack, this will send IP configuration settings to a\r
+ * DHCP client on the network.\r
+ */\r
+\r
+#define INCLUDE_FROM_DHCPSERVERAPP_C\r
+#include "DHCPServerApp.h"\r
+\r
+struct uip_conn* BroadcastConnection;\r
+\r
+uint8_t LeasedIPs[255 / 8];\r
+ \r
+/** Initialization function for the DHCP server. */\r
+void DHCPServerApp_Init(void)\r
+{\r
+ /* Listen on port 67 for DHCP server connections from hosts */\r
+ uip_listen(HTONS(DHCP_SERVER_PORT));\r
+ \r
+ /* Create a new UDP connection to the DHCP server port for the DHCP solicitation */\r
+ struct uip_udp_conn* BroadcastConnection = uip_udp_new(&uip_broadcast_addr, HTONS(DHCP_CLIENT_PORT));\r
+\r
+ /* If the connection was successfully created, bind it to the local DHCP client port */\r
+ if (BroadcastConnection != NULL)\r
+ uip_udp_bind(BroadcastConnection, HTONS(DHCP_SERVER_PORT));\r
+ \r
+ /* Set all IP addresses as unleased */\r
+ memset(LeasedIPs, 0x00, sizeof(LeasedIPs));\r
+}\r
+\r
+/** uIP stack application callback for the DHCP server. This function must be called each time the TCP/IP stack\r
+ * needs a UDP packet to be processed.\r
+ */\r
+void DHCPServerApp_Callback(void)\r
+{\r
+ DHCP_Header_t* const AppData = (DHCP_Header_t*)uip_appdata;\r
+ uint16_t AppDataSize = 0;\r
+\r
+ uint8_t DHCPMessageType;\r
+ if (!(DHCPCommon_GetOption(AppData->Options, DHCP_OPTION_MSG_TYPE, &DHCPMessageType)))\r
+ return;\r
+\r
+ uip_ipaddr_t Netmask, GatewayIPAddress;\r
+ struct uip_eth_addr RemoteMACAddress;\r
+ uint32_t TransactionID;\r
+\r
+ memcpy(&RemoteMACAddress, &AppData->ClientHardwareAddress, sizeof(struct uip_eth_addr));\r
+ uip_getnetmask(&Netmask);\r
+ uip_getdraddr(&GatewayIPAddress); \r
+ TransactionID = AppData->TransactionID;\r
+\r
+ switch (DHCPMessageType)\r
+ {\r
+ case DHCP_DISCOVER:\r
+ AppDataSize += DHCPServerApp_FillDHCPHeader(AppData, DHCP_OFFER, &RemoteMACAddress, TransactionID);\r
+\r
+ AppDataSize += DHCPCommon_SetOption(AppData->Options, DHCP_OPTION_SUBNET_MASK,\r
+ sizeof(uip_ipaddr_t), &Netmask);\r
+ AppDataSize += DHCPCommon_SetOption(AppData->Options, DHCP_OPTION_ROUTER,\r
+ sizeof(uip_ipaddr_t), &GatewayIPAddress);\r
+ \r
+ /* Send the DHCP OFFER packet */\r
+ uip_poll_conn(BroadcastConnection);\r
+ memcpy(&uip_udp_conn->ripaddr, &uip_broadcast_addr, sizeof(uip_ipaddr_t));\r
+ uip_udp_send(AppDataSize);\r
+\r
+ break;\r
+ case DHCP_REQUEST:\r
+ if (!(DHCPServerApp_CheckIfIPLeased(&AppData->YourIP)))\r
+ {\r
+ AppDataSize += DHCPServerApp_FillDHCPHeader(AppData, DHCP_ACK, &RemoteMACAddress, TransactionID);\r
+\r
+ AppDataSize += DHCPCommon_SetOption(AppData->Options, DHCP_OPTION_SUBNET_MASK,\r
+ sizeof(uip_ipaddr_t), &Netmask);\r
+ AppDataSize += DHCPCommon_SetOption(AppData->Options, DHCP_OPTION_ROUTER,\r
+ sizeof(uip_ipaddr_t), &GatewayIPAddress);\r
+\r
+ DHCPServerApp_LeaseIP(&AppData->YourIP);\r
+ }\r
+ else\r
+ {\r
+ AppDataSize += DHCPServerApp_FillDHCPHeader(AppData, DHCP_NAK, &RemoteMACAddress, TransactionID); \r
+ }\r
+ \r
+ /* Send the DHCP ACK or NAK packet */\r
+ uip_poll_conn(BroadcastConnection);\r
+ memcpy(&uip_udp_conn->ripaddr, &uip_broadcast_addr, sizeof(uip_ipaddr_t));\r
+ uip_udp_send(AppDataSize);\r
+ \r
+ break;\r
+ case DHCP_RELEASE:\r
+ /* Mark the IP address as released in the allocation table */\r
+ DHCPServerApp_UnleaseIP(&uip_udp_conn->ripaddr);\r
+ break;\r
+ }\r
+}\r
+\r
+/** Fills the DHCP packet response with the appropriate BOOTP header for DHCP. This fills out all the required\r
+ * fields, leaving only the additional DHCP options to be added to the packet before it is sent to the DHCP client.\r
+ *\r
+ * \param[out] DHCPHeader Location in the packet buffer where the BOOTP header should be written to\r
+ * \param[in] DHCPMessageType DHCP Message type, such as DHCP_DISCOVER\r
+ * \param[in] ClientHardwareAddress Client MAC address the created transaction should be directed to\r
+ * \param[in] TransactionID Transaction ID the created transaction should be associated with\r
+ *\r
+ * \return Size in bytes of the created DHCP packet\r
+ */\r
+static uint16_t DHCPServerApp_FillDHCPHeader(DHCP_Header_t* const DHCPHeader,\r
+ const uint8_t DHCPMessageType,\r
+ struct uip_eth_addr* ClientHardwareAddress,\r
+ uint32_t TransactionID)\r
+{\r
+ /* Erase existing packet data so that we start will all 0x00 DHCP header data */\r
+ memset(DHCPHeader, 0, sizeof(DHCP_Header_t));\r
+\r
+ DHCPHeader->Operation = DHCPMessageType;\r
+ DHCPHeader->HardwareType = DHCP_HTYPE_ETHERNET;\r
+ DHCPHeader->HardwareAddressLength = sizeof(MACAddress);\r
+ DHCPHeader->Hops = 0;\r
+ DHCPHeader->TransactionID = TransactionID;\r
+ DHCPHeader->ElapsedSeconds = 0;\r
+ DHCPHeader->Flags = 0;\r
+ memcpy(&DHCPHeader->NextServerIP, &uip_hostaddr, sizeof(uip_ipaddr_t));\r
+ if (uip_ipaddr_cmp(&DHCPHeader->YourIP, &uip_all_zeroes_addr))\r
+ DHCPServerApp_GetUnleasedIP(&DHCPHeader->YourIP);\r
+ memcpy(&DHCPHeader->ClientHardwareAddress, ClientHardwareAddress, sizeof(struct uip_eth_addr));\r
+ DHCPHeader->Cookie = DHCP_MAGIC_COOKIE;\r
+ \r
+ /* Add a DHCP message type and terminator options to the start of the DHCP options field */\r
+ DHCPHeader->Options[0] = DHCP_OPTION_MSG_TYPE;\r
+ DHCPHeader->Options[1] = 1;\r
+ DHCPHeader->Options[2] = DHCPMessageType;\r
+ DHCPHeader->Options[3] = DHCP_OPTION_END;\r
+\r
+ /* Calculate the total number of bytes added to the outgoing packet */\r
+ return (sizeof(DHCP_Header_t) + 4);\r
+}\r
+\r
+/** Checks to see if the nominated IP address has already been allocated to a client.\r
+ *\r
+ * \param[in] IPAddress IP Address whose lease status should be checked\r
+ *\r
+ * \pre The IP address must be within the same /24 subnet as the virtual webserver.\r
+ *\r
+ * \return Boolean true if the IP has already been leased to a client, false otherwise.\r
+ */\r
+static bool DHCPServerApp_CheckIfIPLeased(uip_ipaddr_t* IPAddress)\r
+{\r
+ uint8_t Byte = (IPAddress->u8[3] / 8);\r
+ uint8_t Mask = (1 << (IPAddress->u8[3] % 8));\r
+ \r
+ if (!(IPAddress->u8[3] == uip_hostaddr.u8[3]) && !(LeasedIPs[Byte] & Mask))\r
+ return false;\r
+ else\r
+ return true;\r
+}\r
+\r
+/** Retrieves the next unleased IP in the IP address pool.\r
+ *\r
+ * \param[out] NewIPAddress Location where the generated IP Address should be stored\r
+ */\r
+static void DHCPServerApp_GetUnleasedIP(uip_ipaddr_t* NewIPAddress)\r
+{\r
+ uip_ipaddr_copy(NewIPAddress, &uip_hostaddr);\r
+ \r
+ for (uint8_t IP = 1; IP < 254; IP++)\r
+ {\r
+ NewIPAddress->u8[3] = IP;\r
+ \r
+ if (!(DHCPServerApp_CheckIfIPLeased(NewIPAddress)))\r
+ return;\r
+ }\r
+}\r
+\r
+/** Marks the given IP Address as leased in the address pool, so that it will not be\r
+ * allocated to another client unless it is first released.\r
+ *\r
+ * \param[in] IPAddress IP Address to mark as leased\r
+ *\r
+ * \pre The IP address must be within the same /24 subnet as the virtual webserver.\r
+ */\r
+static void DHCPServerApp_LeaseIP(uip_ipaddr_t* IPAddress)\r
+{\r
+ uint8_t Byte = (IPAddress->u8[3] / 8);\r
+ uint8_t Mask = (1 << (IPAddress->u8[3] % 8));\r
+ \r
+ LeasedIPs[Byte] |= Mask;\r
+}\r
+\r
+/** Marks the given IP Address as not leased in the address pool, so that it can be\r
+ * allocated to another client upon request.\r
+ *\r
+ * \param[in] IPAddress IP Address to mark as not leased\r
+ *\r
+ * \pre The IP address must be within the same /24 subnet as the virtual webserver.\r
+ */\r
+static void DHCPServerApp_UnleaseIP(uip_ipaddr_t* IPAddress)\r
+{\r
+ uint8_t Byte = (IPAddress->u8[3] / 8);\r
+ uint8_t Mask = (1 << (IPAddress->u8[3] % 8));\r
+ \r
+ LeasedIPs[Byte] &= ~Mask;\r
+}\r
+#endif\r
+\r
projects / pub / USBasp.git / commitdiff