Squashed 'lib/lufa/' content from commit 385d40300

git-subtree-dir: lib/lufa
git-subtree-split: 385d4030035dbaf41591309dbde47653bd03841b

1 files changed, 265 insertions, 0 deletions

diff --git a/Projects/Webserver/Lib/DHCPServerApp.c b/Projects/Webserver/Lib/DHCPServerApp.c
new file mode 100644
index 0000000000..fea54ddb0e
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+++ b/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
+