Sergey Pastor
Webserver+3d print
Diff: cyclone_tcp/core/ethernet.c
- Revision:
- 0:8918a71cdbe9
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/cyclone_tcp/core/ethernet.c Sat Feb 04 18:15:49 2017 +0000
@@ -0,0 +1,1017 @@
+/**
+ * @file ethernet.c
+ * @brief Ethernet
+ *
+ * @section License
+ *
+ * Copyright (C) 2010-2017 Oryx Embedded SARL. All rights reserved.
+ *
+ * This file is part of CycloneTCP Open.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * @author Oryx Embedded SARL (www.oryx-embedded.com)
+ * @version 1.7.6
+ **/
+
+//Switch to the appropriate trace level
+#define TRACE_LEVEL ETH_TRACE_LEVEL
+
+//Dependencies
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include "core/net.h"
+#include "core/nic.h"
+#include "core/ethernet.h"
+#include "core/socket.h"
+#include "core/raw_socket.h"
+#include "core/tcp_timer.h"
+#include "ipv4/arp.h"
+#include "ipv4/ipv4.h"
+#include "ipv6/ipv6.h"
+#include "mibs/mib2_module.h"
+#include "debug.h"
+
+//Check TCP/IP stack configuration
+#if (ETH_SUPPORT == ENABLED)
+
+//Unspecified MAC address
+const MacAddr MAC_UNSPECIFIED_ADDR = {{{0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}};
+//Broadcast MAC address
+const MacAddr MAC_BROADCAST_ADDR = {{{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}}};
+//Unspecified EUI-64 address
+const Eui64 EUI64_UNSPECIFIED_ADDR = {{{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}};
+
+//Padding bytes
+const uint8_t ethPadding[64] =
+{
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+};
+
+//A lookup table can be used to speed up CRC calculation
+#if (ETH_FAST_CRC_SUPPORT == ENABLED)
+
+static const uint32_t crc32Table[256] =
+{
+ 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA,
+ 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
+ 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988,
+ 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
+ 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE,
+ 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
+ 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC,
+ 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
+ 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172,
+ 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
+ 0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940,
+ 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
+ 0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116,
+ 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
+ 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,
+ 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
+ 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A,
+ 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
+ 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818,
+ 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
+ 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E,
+ 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
+ 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C,
+ 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
+ 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2,
+ 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
+ 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0,
+ 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
+ 0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086,
+ 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
+ 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4,
+ 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
+ 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A,
+ 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
+ 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8,
+ 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
+ 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE,
+ 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
+ 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC,
+ 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
+ 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252,
+ 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
+ 0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60,
+ 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
+ 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,
+ 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
+ 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04,
+ 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
+ 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A,
+ 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
+ 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38,
+ 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
+ 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E,
+ 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
+ 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C,
+ 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
+ 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2,
+ 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
+ 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0,
+ 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
+ 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6,
+ 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
+ 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94,
+ 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
+};
+
+#endif
+
+
+/**
+ * @brief Ethernet related initialization
+ * @param[in] interface Underlying network interface
+ * @return Error code
+ **/
+
+error_t ethInit(NetInterface *interface)
+{
+ //Clear the MAC filter table contents
+ memset(interface->macMulticastFilter, 0,
+ sizeof(interface->macMulticastFilter));
+
+ //Successful initialization
+ return NO_ERROR;
+}
+
+
+/**
+ * @brief Process an incoming Ethernet frame
+ * @param[in] interface Underlying network interface
+ * @param[in] ethFrame Incoming Ethernet frame to process
+ * @param[in] length Total frame length
+ **/
+
+void ethProcessFrame(NetInterface *interface, EthHeader *ethFrame, size_t length)
+{
+#if (IPV6_SUPPORT == ENABLED)
+ NetBuffer1 buffer;
+#endif
+ uint32_t crc;
+
+ //Total number of octets received on the interface
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifInOctets, length);
+
+ //Ensure the length of the incoming frame is valid
+ if(length < sizeof(EthHeader))
+ {
+ //Number of inbound packets that contained errors
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifInErrors, 1);
+ //Discard the received frame
+ return;
+ }
+
+ //Debug message
+ TRACE_DEBUG("Ethernet frame received (%" PRIuSIZE " bytes)...\r\n", length);
+ //Dump Ethernet header contents for debugging purpose
+ ethDumpHeader(ethFrame);
+
+ //Check whether the CRC is included in the received frame
+ if(!interface->nicDriver->autoCrcStrip)
+ {
+ //Ensure the length of the incoming frame is valid
+ if(length < (sizeof(EthHeader) + ETH_CRC_SIZE))
+ {
+ //Number of inbound packets that contained errors
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifInErrors, 1);
+ //Discard the received frame
+ return;
+ }
+
+ //CRC verification not supported by hardware?
+ if(!interface->nicDriver->autoCrcVerif)
+ {
+ //The value of the residue is 0x2144DF1C when no CRC errors are detected
+ if(ethCalcCrc(ethFrame, length) != 0x2144DF1C)
+ {
+ //Debug message
+ TRACE_WARNING("Wrong CRC detected!\r\n");
+ //Number of inbound packets that contained errors
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifInErrors, 1);
+ //Discard the received frame
+ return;
+ }
+ }
+
+ //Retrieve CRC value
+ memcpy(&crc, (uint8_t *) ethFrame + length - ETH_CRC_SIZE, ETH_CRC_SIZE);
+ //Reseed the pseudo-random number generator
+ netInitRand(crc);
+ }
+
+ //Frame filtering based on destination MAC address
+ if(ethCheckDestAddr(interface, ðFrame->destAddr))
+ {
+ //Number of inbound packets which were chosen to be discarded
+ //even though no errors had been detected
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifInDiscards, 1);
+ //Discard the received frame
+ return;
+ }
+
+ //Check whether the destination address is a group address
+ if(macIsMulticastAddr(ðFrame->destAddr))
+ {
+ //Number of non-unicast packets delivered to a higher-layer protocol
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifInNUcastPkts, 1);
+ }
+ else
+ {
+ //Number of unicast packets delivered to a higher-layer protocol
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifInUcastPkts, 1);
+ }
+
+#if (RAW_SOCKET_SUPPORT == ENABLED)
+ //Allow raw sockets to process Ethernet packets
+ rawSocketProcessEthPacket(interface, ethFrame, length - ETH_CRC_SIZE);
+#endif
+
+ //Calculate the length of the data payload
+ length -= sizeof(EthHeader);
+
+ //Check whether the CRC is included in the received frame
+ if(!interface->nicDriver->autoCrcStrip)
+ length -= ETH_CRC_SIZE;
+
+ //Check Ethernet type field
+ switch(ntohs(ethFrame->type))
+ {
+#if (IPV4_SUPPORT == ENABLED)
+ //ARP packet received?
+ case ETH_TYPE_ARP:
+ //Process incoming ARP packet
+ arpProcessPacket(interface, (ArpPacket *) ethFrame->data, length);
+ break;
+ //IPv4 packet received?
+ case ETH_TYPE_IPV4:
+ //Process incoming IPv4 packet
+ ipv4ProcessPacket(interface, (Ipv4Header *) ethFrame->data, length);
+ break;
+#endif
+
+#if (IPV6_SUPPORT == ENABLED)
+ //IPv6 packet received?
+ case ETH_TYPE_IPV6:
+ //The incoming Ethernet frame fits in a single chunk
+ buffer.chunkCount = 1;
+ buffer.maxChunkCount = 1;
+ buffer.chunk[0].address = ethFrame->data;
+ buffer.chunk[0].length = length;
+ buffer.chunk[0].size = 0;
+
+ //Process incoming IPv6 packet
+ ipv6ProcessPacket(interface, (NetBuffer *) &buffer, 0);
+ break;
+#endif
+
+ //Unknown packet received?
+ default:
+ //Debug message
+ TRACE_WARNING("Unknown Ethernet type!\r\n");
+
+ //Number of packets received via the interface which were
+ //discarded because of an unknown or unsupported protocol
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifInUnknownProtos , 1);
+ break;
+ }
+}
+
+
+/**
+ * @brief Send an Ethernet frame
+ * @param[in] interface Underlying network interface
+ * @param[in] destAddr MAC address of the destination host
+ * @param[in] buffer Multi-part buffer containing the payload
+ * @param[in] offset Offset to the first payload byte
+ * @param[in] type Ethernet type
+ * @return Error code
+ **/
+
+error_t ethSendFrame(NetInterface *interface, const MacAddr *destAddr,
+ NetBuffer *buffer, size_t offset, uint16_t type)
+{
+ error_t error;
+ size_t length;
+ EthHeader *header;
+
+ //Is there enough space for the Ethernet header?
+ if(offset < sizeof(EthHeader))
+ return ERROR_INVALID_PARAMETER;
+
+ //Make room for the Ethernet header
+ offset -= sizeof(EthHeader);
+ //Retrieve the length of the frame
+ length = netBufferGetLength(buffer) - offset;
+
+ //Position to the beginning of the frame
+ header = netBufferAt(buffer, offset);
+
+ //Format Ethernet header
+ header->destAddr = *destAddr;
+ header->srcAddr = interface->macAddr;
+ header->type = htons(type);
+
+ //Automatic padding not supported by hardware?
+ if(!interface->nicDriver->autoPadding)
+ {
+ //The host controller should manually add padding
+ //to the packet before transmitting it
+ if(length < (ETH_MIN_FRAME_SIZE - ETH_CRC_SIZE))
+ {
+ size_t n;
+
+ //Add padding as necessary
+ n = (ETH_MIN_FRAME_SIZE - ETH_CRC_SIZE) - length;
+
+ //Append padding bytes
+ error = netBufferAppend(buffer, ethPadding, n);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Adjust frame length
+ length += n;
+ }
+ }
+
+ //CRC calculation not supported by hardware?
+ if(!interface->nicDriver->autoCrcCalc)
+ {
+ uint32_t crc;
+
+ //Compute CRC over the header and payload
+ crc = ethCalcCrcEx(buffer, offset, length);
+ //Convert from host byte order to little-endian byte order
+ crc = htole32(crc);
+
+ //Append the calculated CRC value
+ error = netBufferAppend(buffer, &crc, sizeof(crc));
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Adjust frame length
+ length += sizeof(crc);
+ }
+
+ //Total number of octets transmitted out of the interface
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifOutOctets, length);
+
+ //Check whether the destination address is a group address
+ if(macIsMulticastAddr(&header->destAddr))
+ {
+ //Total number of non-unicast packets that higher-level protocols
+ //requested be transmitted
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifOutNUcastPkts, 1);
+ }
+ else
+ {
+ //Total number of unicast packets that higher-level protocols
+ //requested be transmitted
+ MIB2_INC_COUNTER32(interface->mibIfEntry->ifOutUcastPkts, 1);
+ }
+
+ //Debug message
+ TRACE_DEBUG("Sending Ethernet frame (%" PRIuSIZE " bytes)...\r\n", length);
+ //Dump Ethernet header contents for debugging purpose
+ ethDumpHeader(header);
+
+ //Send the resulting packet over the specified link
+ error = nicSendPacket(interface, buffer, offset);
+ //Return status code
+ return error;
+}
+
+
+/**
+ * @brief Destination MAC address filtering
+ * @param[in] interface Underlying network interface
+ * @param[in] macAddr Destination MAC address to be checked
+ * @return Error code
+ **/
+
+error_t ethCheckDestAddr(NetInterface *interface, const MacAddr *macAddr)
+{
+ uint_t i;
+ MacFilterEntry *entry;
+
+ //Filter out any invalid addresses
+ error_t error = ERROR_INVALID_ADDRESS;
+
+ //Host address?
+ if(macCompAddr(macAddr, &interface->macAddr))
+ {
+ error = NO_ERROR;
+ }
+ //Broadcast address?
+ else if(macCompAddr(macAddr, &MAC_BROADCAST_ADDR))
+ {
+ error = NO_ERROR;
+ }
+ //Multicast address?
+ else if(macIsMulticastAddr(macAddr))
+ {
+ //Go through the multicast filter table
+ for(i = 0; i < MAC_MULTICAST_FILTER_SIZE; i++)
+ {
+ //Point to the current entry
+ entry = &interface->macMulticastFilter[i];
+
+ //Valid entry?
+ if(entry->refCount > 0)
+ {
+ //Check whether the destination MAC address matches
+ //a relevant multicast address
+ if(macCompAddr(&entry->addr, macAddr))
+ {
+ //The MAC address is acceptable
+ error = NO_ERROR;
+ //Stop immediately
+ break;
+ }
+ }
+ }
+ }
+
+ //Return status code
+ return error;
+}
+
+
+/**
+ * @brief Add a multicast address to the MAC filter table
+ * @param[in] interface Underlying network interface
+ * @param[in] macAddr Multicast MAC address to accept
+ * @return Error code
+ **/
+
+error_t ethAcceptMulticastAddr(NetInterface *interface, const MacAddr *macAddr)
+{
+ uint_t i;
+ MacFilterEntry *entry;
+ MacFilterEntry *firstFreeEntry;
+
+ //Keep track of the first free entry
+ firstFreeEntry = NULL;
+
+ //Go through the multicast filter table
+ for(i = 0; i < MAC_MULTICAST_FILTER_SIZE; i++)
+ {
+ //Point to the current entry
+ entry = &interface->macMulticastFilter[i];
+
+ //Valid entry?
+ if(entry->refCount > 0)
+ {
+ //Check whether the table already contains the specified MAC address
+ if(macCompAddr(&entry->addr, macAddr))
+ {
+ //Increment the reference count
+ entry->refCount++;
+ //No error to report
+ return NO_ERROR;
+ }
+ }
+ else
+ {
+ //Keep track of the first free entry
+ if(firstFreeEntry == NULL)
+ firstFreeEntry = entry;
+ }
+ }
+
+ //Check whether the multicast filter table is full
+ if(firstFreeEntry == NULL)
+ {
+ //A new entry cannot be added
+ return ERROR_FAILURE;
+ }
+
+ //Add a new entry to the table
+ firstFreeEntry->addr = *macAddr;
+ //Initialize the reference count
+ firstFreeEntry->refCount = 1;
+
+ //Force the network interface controller to add the current
+ //entry to its MAC filter table
+ firstFreeEntry->addFlag = TRUE;
+ firstFreeEntry->deleteFlag = FALSE;
+
+ //Update the MAC filter table
+ nicSetMulticastFilter(interface);
+
+ //Clear the flag
+ firstFreeEntry->addFlag = FALSE;
+
+ //No error to report
+ return NO_ERROR;
+}
+
+
+/**
+ * @brief Remove a multicast address from the MAC filter table
+ * @param[in] interface Underlying network interface
+ * @param[in] macAddr Multicast MAC address to drop
+ * @return Error code
+ **/
+
+error_t ethDropMulticastAddr(NetInterface *interface, const MacAddr *macAddr)
+{
+ uint_t i;
+ MacFilterEntry *entry;
+
+ //Go through the multicast filter table
+ for(i = 0; i < MAC_MULTICAST_FILTER_SIZE; i++)
+ {
+ //Point to the current entry
+ entry = &interface->macMulticastFilter[i];
+
+ //Valid entry?
+ if(entry->refCount > 0)
+ {
+ //Specified MAC address found?
+ if(macCompAddr(&entry->addr, macAddr))
+ {
+ //Decrement the reference count
+ entry->refCount--;
+
+ //Remove the entry if the reference count drops to zero
+ if(entry->refCount == 0)
+ {
+ //Force the network interface controller to remove the current
+ //entry from its MAC filter table
+ entry->deleteFlag = TRUE;
+
+ //Update the MAC filter table
+ nicSetMulticastFilter(interface);
+
+ //Clear the flag
+ entry->deleteFlag = FALSE;
+ //Remove the multicast address from the list
+ entry->addr = MAC_UNSPECIFIED_ADDR;
+ }
+
+ //No error to report
+ return NO_ERROR;
+ }
+ }
+ }
+
+ //The specified MAC address does not exist
+ return ERROR_ADDRESS_NOT_FOUND;
+}
+
+
+/**
+ * @brief Ethernet CRC calculation
+ * @param[in] data Pointer to the data over which to calculate the CRC
+ * @param[in] length Number of bytes to process
+ * @return Resulting CRC value
+ **/
+
+uint32_t ethCalcCrc(const void *data, size_t length)
+{
+//A lookup table can be used to speed up CRC calculation
+#if (ETH_FAST_CRC_SUPPORT == ENABLED)
+ uint_t i;
+
+ //Point to the data over which to calculate the CRC
+ const uint8_t *p = (uint8_t *) data;
+ //CRC preset value
+ uint32_t crc = 0xFFFFFFFF;
+
+ //Loop through data
+ for(i = 0; i < length; i++)
+ {
+ //The message is processed byte by byte
+ crc = (crc >> 8) ^ crc32Table[(crc & 0xFF) ^ p[i]];
+ }
+
+ //Return 1's complement value
+ return ~crc;
+
+//Bit by bit CRC calculation
+#else
+ uint_t i;
+ uint_t j;
+
+ //Point to the data over which to calculate the CRC
+ const uint8_t *p = (uint8_t *) data;
+ //CRC preset value
+ uint32_t crc = 0xFFFFFFFF;
+
+ //Loop through data
+ for(i = 0; i < length; i++)
+ {
+ //Update CRC value
+ crc ^= p[i];
+ //The message is processed bit by bit
+ for(j = 0; j < 8; j++)
+ {
+ if(crc & 0x00000001)
+ crc = (crc >> 1) ^ 0xEDB88320;
+ else
+ crc = crc >> 1;
+ }
+ }
+
+ //Return 1's complement value
+ return ~crc;
+#endif
+}
+
+
+/**
+ * @brief Calculate CRC over a multi-part buffer
+ * @param[in] buffer Pointer to the multi-part buffer
+ * @param[in] offset Offset from the beginning of the buffer
+ * @param[in] length Number of bytes to process
+ * @return Resulting CRC value
+ **/
+
+uint32_t ethCalcCrcEx(const NetBuffer *buffer, size_t offset, size_t length)
+{
+ uint_t i;
+ uint_t n;
+ uint32_t crc;
+ uint8_t *p;
+#if (ETH_FAST_CRC_SUPPORT == DISABLED)
+ uint_t k;
+#endif
+
+ //CRC preset value
+ crc = 0xFFFFFFFF;
+
+ //Loop through data chunks
+ for(i = 0; i < buffer->chunkCount && length > 0; i++)
+ {
+ //Is there any data to process in the current chunk?
+ if(offset < buffer->chunk[i].length)
+ {
+ //Point to the first data byte
+ p = (uint8_t *) buffer->chunk[i].address + offset;
+ //Compute the number of bytes to process
+ n = MIN(buffer->chunk[i].length - offset, length);
+ //Adjust byte counter
+ length -= n;
+
+ //Process current chunk
+ while(n > 0)
+ {
+#if (ETH_FAST_CRC_SUPPORT == ENABLED)
+ //The message is processed byte by byte
+ crc = (crc >> 8) ^ crc32Table[(crc & 0xFF) ^ *p];
+#else
+ //Update CRC value
+ crc ^= *p;
+
+ //The message is processed bit by bit
+ for(k = 0; k < 8; k++)
+ {
+ if(crc & 0x00000001)
+ crc = (crc >> 1) ^ 0xEDB88320;
+ else
+ crc = crc >> 1;
+ }
+#endif
+ //Next byte
+ p++;
+ n--;
+ }
+
+ //Process the next block from the start
+ offset = 0;
+ }
+ else
+ {
+ //Skip the current chunk
+ offset -= buffer->chunk[i].length;
+ }
+ }
+
+ //Return 1's complement value
+ return ~crc;
+}
+
+
+/**
+ * @brief Allocate a buffer to hold an Ethernet frame
+ * @param[in] length Desired payload length
+ * @param[out] offset Offset to the first byte of the payload
+ * @return The function returns a pointer to the newly allocated
+ * buffer. If the system is out of resources, NULL is returned
+ **/
+
+NetBuffer *ethAllocBuffer(size_t length, size_t *offset)
+{
+ NetBuffer *buffer;
+
+ //Allocate a buffer to hold the Ethernet header and the payload
+ buffer = netBufferAlloc(length + sizeof(EthHeader));
+ //Failed to allocate buffer?
+ if(buffer == NULL)
+ return NULL;
+
+ //Offset to the first byte of the payload
+ *offset = sizeof(EthHeader);
+
+ //Return a pointer to the freshly allocated buffer
+ return buffer;
+}
+
+
+/**
+ * @brief Convert a string representation of a MAC address to a binary MAC address
+ * @param[in] str NULL-terminated string representing the MAC address
+ * @param[out] macAddr Binary representation of the MAC address
+ * @return Error code
+ **/
+
+error_t macStringToAddr(const char_t *str, MacAddr *macAddr)
+{
+ error_t error;
+ int_t i = 0;
+ int_t value = -1;
+
+ //Parse input string
+ while(1)
+ {
+ //Hexadecimal digit found?
+ if(isxdigit((uint8_t) *str))
+ {
+ //First digit to be decoded?
+ if(value < 0) value = 0;
+ //Update the value of the current byte
+ if(isdigit((uint8_t) *str))
+ value = (value * 16) + (*str - '0');
+ else if(isupper((uint8_t) *str))
+ value = (value * 16) + (*str - 'A' + 10);
+ else
+ value = (value * 16) + (*str - 'a' + 10);
+ //Check resulting value
+ if(value > 0xFF)
+ {
+ //The conversion failed
+ error = ERROR_INVALID_SYNTAX;
+ break;
+ }
+ }
+ //Dash or colon separator found?
+ else if((*str == '-' || *str == ':') && i < 6)
+ {
+ //Each separator must be preceded by a valid number
+ if(value < 0)
+ {
+ //The conversion failed
+ error = ERROR_INVALID_SYNTAX;
+ break;
+ }
+
+ //Save the current byte
+ macAddr->b[i++] = value;
+ //Prepare to decode the next byte
+ value = -1;
+ }
+ //End of string detected?
+ else if(*str == '\0' && i == 5)
+ {
+ //The NULL character must be preceded by a valid number
+ if(value < 0)
+ {
+ //The conversion failed
+ error = ERROR_INVALID_SYNTAX;
+ }
+ else
+ {
+ //Save the last byte of the MAC address
+ macAddr->b[i] = value;
+ //The conversion succeeded
+ error = NO_ERROR;
+ }
+
+ //We are done
+ break;
+ }
+ //Invalid character...
+ else
+ {
+ //The conversion failed
+ error = ERROR_INVALID_SYNTAX;
+ break;
+ }
+
+ //Point to the next character
+ str++;
+ }
+
+ //Return status code
+ return error;
+}
+
+
+/**
+ * @brief Convert a MAC address to a dash delimited string
+ * @param[in] macAddr Pointer to the MAC address
+ * @param[out] str NULL-terminated string representing the MAC address
+ * @return Pointer to the formatted string
+ **/
+
+char_t *macAddrToString(const MacAddr *macAddr, char_t *str)
+{
+ static char_t buffer[18];
+
+ //The str parameter is optional
+ if(str == NULL)
+ str = buffer;
+
+ //Format MAC address
+ sprintf(str, "%02" PRIX8 "-%02" PRIX8 "-%02" PRIX8 "-%02" PRIX8 "-%02" PRIX8 "-%02" PRIX8,
+ macAddr->b[0], macAddr->b[1], macAddr->b[2], macAddr->b[3], macAddr->b[4], macAddr->b[5]);
+
+ //Return a pointer to the formatted string
+ return str;
+}
+
+
+/**
+ * @brief Convert a string representation of an EUI-64 address to a binary EUI-64 address
+ * @param[in] str NULL-terminated string representing the EUI-64 address
+ * @param[out] eui64 Binary representation of the EUI-64 address
+ * @return Error code
+ **/
+
+error_t eui64StringToAddr(const char_t *str, Eui64 *eui64)
+{
+ error_t error;
+ int_t i = 0;
+ int_t value = -1;
+
+ //Parse input string
+ while(1)
+ {
+ //Hexadecimal digit found?
+ if(isxdigit((uint8_t) *str))
+ {
+ //First digit to be decoded?
+ if(value < 0) value = 0;
+ //Update the value of the current byte
+ if(isdigit((uint8_t) *str))
+ value = (value * 16) + (*str - '0');
+ else if(isupper((uint8_t) *str))
+ value = (value * 16) + (*str - 'A' + 10);
+ else
+ value = (value * 16) + (*str - 'a' + 10);
+ //Check resulting value
+ if(value > 0xFF)
+ {
+ //The conversion failed
+ error = ERROR_INVALID_SYNTAX;
+ break;
+ }
+ }
+ //Dash or colon separator found?
+ else if((*str == '-' || *str == ':') && i < 8)
+ {
+ //Each separator must be preceded by a valid number
+ if(value < 0)
+ {
+ //The conversion failed
+ error = ERROR_INVALID_SYNTAX;
+ break;
+ }
+
+ //Save the current byte
+ eui64->b[i++] = value;
+ //Prepare to decode the next byte
+ value = -1;
+ }
+ //End of string detected?
+ else if(*str == '\0' && i == 7)
+ {
+ //The NULL character must be preceded by a valid number
+ if(value < 0)
+ {
+ //The conversion failed
+ error = ERROR_INVALID_SYNTAX;
+ }
+ else
+ {
+ //Save the last byte of the EUI-64 address
+ eui64->b[i] = value;
+ //The conversion succeeded
+ error = NO_ERROR;
+ }
+
+ //We are done
+ break;
+ }
+ //Invalid character...
+ else
+ {
+ //The conversion failed
+ error = ERROR_INVALID_SYNTAX;
+ break;
+ }
+
+ //Point to the next character
+ str++;
+ }
+
+ //Return status code
+ return error;
+}
+
+
+/**
+ * @brief Convert an EUI-64 address to a dash delimited string
+ * @param[in] eui64 Pointer to the EUI-64 address
+ * @param[out] str NULL-terminated string representing the EUI-64 address
+ * @return Pointer to the formatted string
+ **/
+
+char_t *eui64AddrToString(const Eui64 *eui64, char_t *str)
+{
+ static char_t buffer[24];
+
+ //The str parameter is optional
+ if(str == NULL)
+ str = buffer;
+
+ //Format EUI-64 identifier
+ sprintf(str, "%02" PRIX8 "-%02" PRIX8 "-%02" PRIX8 "-%02" PRIX8
+ "-%02" PRIX8 "-%02" PRIX8 "-%02" PRIX8 "-%02" PRIX8,
+ eui64->b[0], eui64->b[1], eui64->b[2], eui64->b[3],
+ eui64->b[4], eui64->b[5], eui64->b[6], eui64->b[7]);
+
+ //Return a pointer to the formatted string
+ return str;
+}
+
+
+/**
+ * @brief Map a MAC address to the IPv6 modified EUI-64 identifier
+ * @param[in] macAddr Host MAC address
+ * @param[out] interfaceId IPv6 modified EUI-64 identifier
+ **/
+
+void macAddrToEui64(const MacAddr *macAddr, Eui64 *interfaceId)
+{
+ //Copy the Organization Unique Identifier (OUI)
+ interfaceId->b[0] = macAddr->b[0];
+ interfaceId->b[1] = macAddr->b[1];
+ interfaceId->b[2] = macAddr->b[2];
+
+ //The middle 16 bits are given the value 0xFFFE
+ interfaceId->b[3] = 0xFF;
+ interfaceId->b[4] = 0xFE;
+
+ //Copy the right-most 24 bits of the MAC address
+ interfaceId->b[5] = macAddr->b[3];
+ interfaceId->b[6] = macAddr->b[4];
+ interfaceId->b[7] = macAddr->b[5];
+
+ //Modified EUI-64 format interface identifiers are
+ //formed by inverting the Universal/Local bit
+ interfaceId->b[0] ^= MAC_ADDR_FLAG_LOCAL;
+}
+
+
+/**
+ * @brief Dump Ethernet header for debugging purpose
+ * @param[in] ethHeader Pointer to the Ethernet header
+ **/
+
+void ethDumpHeader(const EthHeader *ethHeader)
+{
+ //Dump Ethernet header contents
+ TRACE_DEBUG(" Dest Addr = %s\r\n", macAddrToString(ðHeader->destAddr, NULL));
+ TRACE_DEBUG(" Src Addr = %s\r\n", macAddrToString(ðHeader->srcAddr, NULL));
+ TRACE_DEBUG(" Type = 0x%04" PRIX16 "\r\n", ntohs(ethHeader->type));
+}
+
+#endif
+