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diff --git a/lib/lufa/Projects/Webserver/Lib/DHCPServerApp.c b/lib/lufa/Projects/Webserver/Lib/DHCPServerApp.c
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+++ b/lib/lufa/Projects/Webserver/Lib/DHCPServerApp.c
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+/*
+ 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 Server Application. When connected to the uIP stack, this will send IP configuration settings to a
+ * DHCP client on the network.
+ */
+
+#define INCLUDE_FROM_DHCPSERVERAPP_C
+#include "DHCPServerApp.h"
+
+#if defined(ENABLE_DHCP_SERVER) || defined(__DOXYGEN__)
+
+struct uip_conn* BroadcastConnection;
+
+uint8_t LeasedIPs[255 / 8];
+
+/** Initialization function for the DHCP server. */
+void DHCPServerApp_Init(void)
+{
+ /* Listen on port 67 for DHCP server connections from hosts */
+ uip_listen(HTONS(DHCP_SERVER_PORT));
+
+ /* Create a new UDP connection to the DHCP server port for the DHCP solicitation */
+ struct uip_udp_conn* BroadcastConnection = uip_udp_new(&uip_broadcast_addr, HTONS(DHCP_CLIENT_PORT));
+
+ /* If the connection was successfully created, bind it to the local DHCP client port */
+ if (BroadcastConnection != NULL)
+ uip_udp_bind(BroadcastConnection, HTONS(DHCP_SERVER_PORT));
+
+ /* Set all IP addresses as unleased */
+ memset(LeasedIPs, 0x00, sizeof(LeasedIPs));
+}
+
+/** uIP stack application callback for the DHCP server. This function must be called each time the TCP/IP stack
+ * needs a UDP packet to be processed.
+ */
+void DHCPServerApp_Callback(void)
+{
+ DHCP_Header_t* const AppData = (DHCP_Header_t*)uip_appdata;
+ uint16_t AppDataSize = 0;
+
+ /* Only process when new data arrives - don't retransmit lost packets */
+ if (uip_newdata())
+ {
+ /* Get the DHCP message type (if present), otherwise early-abort */
+ uint8_t DHCPMessageType;
+ if (!(DHCPCommon_GetOption(AppData->Options, DHCP_OPTION_MSG_TYPE, &DHCPMessageType)))
+ return;
+
+ uip_ipaddr_t Netmask, GatewayIPAddress, PreferredClientIP;
+ struct uip_eth_addr RemoteMACAddress;
+ uint32_t TransactionID;
+
+ /* Get configured network mask, gateway IP and extract out DHCP transaction ID and remote IP */
+ uip_getnetmask(&Netmask);
+ uip_getdraddr(&GatewayIPAddress);
+ memcpy(&RemoteMACAddress, &AppData->ClientHardwareAddress, sizeof(struct uip_eth_addr));
+ TransactionID = AppData->TransactionID;
+
+ /* Try to extract out the client's preferred IP address if it is indicated in the packet */
+ if (!(DHCPCommon_GetOption(AppData->Options, DHCP_OPTION_REQ_IPADDR, &PreferredClientIP)))
+ memcpy(&PreferredClientIP, &uip_all_zeroes_addr, sizeof(uip_ipaddr_t));
+
+ switch (DHCPMessageType)
+ {
+ case DHCP_DISCOVER:
+ /* If no preference was made or the preferred IP is already taken, find a new address */
+ if (DHCPServerApp_CheckIfIPLeased(&PreferredClientIP))
+ DHCPServerApp_GetUnleasedIP(&PreferredClientIP);
+
+ /* Create a new DHCP OFFER packet with the offered IP address */
+ AppDataSize += DHCPServerApp_FillDHCPHeader(AppData, DHCP_OFFER, &RemoteMACAddress, &PreferredClientIP, TransactionID);
+
+ /* Add network mask and router information to the list of DHCP OFFER packet options */
+ AppDataSize += DHCPCommon_SetOption(AppData->Options, DHCP_OPTION_SUBNET_MASK,
+ sizeof(uip_ipaddr_t), &Netmask);
+ AppDataSize += DHCPCommon_SetOption(AppData->Options, DHCP_OPTION_ROUTER,
+ sizeof(uip_ipaddr_t), &GatewayIPAddress);
+
+ /* Send the DHCP OFFER packet */
+ uip_poll_conn(BroadcastConnection);
+ memcpy(&uip_udp_conn->ripaddr, &uip_broadcast_addr, sizeof(uip_ipaddr_t));
+ uip_udp_send(AppDataSize);
+
+ break;
+ case DHCP_REQUEST:
+ /* Check to see if the requested IP address has already been leased to a client */
+ if (!(DHCPServerApp_CheckIfIPLeased(&PreferredClientIP)))
+ {
+ /* Create a new DHCP ACK packet to accept the IP address lease */
+ AppDataSize += DHCPServerApp_FillDHCPHeader(AppData, DHCP_ACK, &RemoteMACAddress, &PreferredClientIP, TransactionID);
+
+ /* Add network mask and router information to the list of DHCP ACK packet options */
+ AppDataSize += DHCPCommon_SetOption(AppData->Options, DHCP_OPTION_SUBNET_MASK,
+ sizeof(uip_ipaddr_t), &Netmask);
+ AppDataSize += DHCPCommon_SetOption(AppData->Options, DHCP_OPTION_ROUTER,
+ sizeof(uip_ipaddr_t), &GatewayIPAddress);
+
+ /* Mark the requested IP as leased to a client */
+ DHCPServerApp_LeaseIP(&PreferredClientIP);
+ }
+ else
+ {
+ /* Create a new DHCP NAK packet to reject the requested allocation */
+ AppDataSize += DHCPServerApp_FillDHCPHeader(AppData, DHCP_NAK, &RemoteMACAddress, &uip_all_zeroes_addr, TransactionID);
+ }
+
+ /* Send the DHCP ACK or NAK packet */
+ uip_poll_conn(BroadcastConnection);
+ memcpy(&uip_udp_conn->ripaddr, &uip_broadcast_addr, sizeof(uip_ipaddr_t));
+ uip_udp_send(AppDataSize);
+
+ break;
+ case DHCP_RELEASE:
+ /* Mark the IP address as released in the allocation table */
+ DHCPServerApp_UnleaseIP(&uip_udp_conn->ripaddr);
+ 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 client.
+ *
+ * \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] ClientHardwareAddress Client MAC address the created transaction should be directed to
+ * \param[in] PreferredClientIP Preferred IP that should be given to the client if it is unallocated
+ * \param[in] TransactionID Transaction ID the created transaction should be associated with
+ *
+ * \return Size in bytes of the created DHCP packet
+ */
+static uint16_t DHCPServerApp_FillDHCPHeader(DHCP_Header_t* const DHCPHeader,
+ const uint8_t DHCPMessageType,
+ const struct uip_eth_addr* const ClientHardwareAddress,
+ const uip_ipaddr_t* const PreferredClientIP,
+ const uint32_t TransactionID)
+{
+ /* Erase existing packet data so that we start will all 0x00 DHCP header data */
+ memset(DHCPHeader, 0, sizeof(DHCP_Header_t));
+
+ DHCPHeader->Operation = DHCPMessageType;
+ DHCPHeader->HardwareType = DHCP_HTYPE_ETHERNET;
+ DHCPHeader->HardwareAddressLength = sizeof(MACAddress);
+ DHCPHeader->Hops = 0;
+ DHCPHeader->TransactionID = TransactionID;
+ DHCPHeader->ElapsedSeconds = 0;
+ DHCPHeader->Flags = 0;
+ memcpy(&DHCPHeader->NextServerIP, &uip_hostaddr, sizeof(uip_ipaddr_t));
+ memcpy(&DHCPHeader->YourIP, PreferredClientIP, sizeof(uip_ipaddr_t));
+ memcpy(&DHCPHeader->ClientHardwareAddress, ClientHardwareAddress, 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);
+}
+
+/** Checks to see if the nominated IP address has already been allocated to a client.
+ *
+ * \param[in] IPAddress IP Address whose lease status should be checked
+ *
+ * \pre The IP address must be within the same /24 subnet as the virtual webserver.
+ *
+ * \return Boolean \c true if the IP has already been leased to a client, \c false otherwise.
+ */
+static bool DHCPServerApp_CheckIfIPLeased(const uip_ipaddr_t* const IPAddress)
+{
+ uint8_t Byte = (IPAddress->u8[3] / 8);
+ uint8_t Mask = (1 << (IPAddress->u8[3] % 8));
+
+ /* Make sure that the requested IP address isn't already leased to the virtual server or another client */
+ if (IPAddress->u8[3] && !(IPAddress->u8[3] == uip_hostaddr.u8[3]) && !(LeasedIPs[Byte] & Mask))
+ return false;
+ else
+ return true;
+}
+
+/** Retrieves the next unleased IP in the IP address pool.
+ *
+ * \param[out] NewIPAddress Location where the generated IP Address should be stored
+ */
+static void DHCPServerApp_GetUnleasedIP(uip_ipaddr_t* const NewIPAddress)
+{
+ uip_ipaddr_copy(NewIPAddress, &uip_hostaddr);
+
+ /** Look through the current subnet, skipping the broadcast and zero IP addresses */
+ for (uint8_t IP = 1; IP < 254; IP++)
+ {
+ /* Update new IP address to lease with the current IP address to test */
+ NewIPAddress->u8[3] = IP;
+
+ /* If we've found an unleased IP, abort with the updated IP stored for the called */
+ if (!(DHCPServerApp_CheckIfIPLeased(NewIPAddress)))
+ return;
+ }
+}
+
+/** Marks the given IP Address as leased in the address pool, so that it will not be
+ * allocated to another client unless it is first released.
+ *
+ * \param[in] IPAddress IP Address to mark as leased
+ *
+ * \pre The IP address must be within the same /24 subnet as the virtual webserver.
+ */
+static void DHCPServerApp_LeaseIP(const uip_ipaddr_t* const IPAddress)
+{
+ uint8_t Byte = (IPAddress->u8[3] / 8);
+ uint8_t Mask = (1 << (IPAddress->u8[3] % 8));
+
+ /* Mark the IP address as leased in the allocation table */
+ LeasedIPs[Byte] |= Mask;
+}
+
+/** Marks the given IP Address as not leased in the address pool, so that it can be
+ * allocated to another client upon request.
+ *
+ * \param[in] IPAddress IP Address to mark as not leased
+ *
+ * \pre The IP address must be within the same /24 subnet as the virtual webserver.
+ */
+static void DHCPServerApp_UnleaseIP(const uip_ipaddr_t* const IPAddress)
+{
+ uint8_t Byte = (IPAddress->u8[3] / 8);
+ uint8_t Mask = (1 << (IPAddress->u8[3] % 8));
+
+ /* Mark the IP address as unleased in the allocation table */
+ LeasedIPs[Byte] &= ~Mask;
+}
+#endif
+