arp.h

00001 /**
00002  * @file arp.h
00003  * @brief ARP (Address Resolution Protocol)
00004  *
00005  * @section License
00006  *
00007  * Copyright (C) 2010-2017 Oryx Embedded SARL. All rights reserved.
00008  *
00009  * This file is part of CycloneTCP Open.
00010  *
00011  * This program is free software; you can redistribute it and/or
00012  * modify it under the terms of the GNU General Public License
00013  * as published by the Free Software Foundation; either version 2
00014  * of the License, or (at your option) any later version.
00015  *
00016  * This program is distributed in the hope that it will be useful,
00017  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00018  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00019  * GNU General Public License for more details.
00020  *
00021  * You should have received a copy of the GNU General Public License
00022  * along with this program; if not, write to the Free Software Foundation,
00023  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
00024  *
00025  * @author Oryx Embedded SARL (www.oryx-embedded.com)
00026  * @version 1.7.6
00027  **/
00028 
00029 #ifndef _ARP_H
00030 #define _ARP_H
00031 
00032 //Dependencies
00033 #include "core/net.h"
00034 
00035 //ARP tick interval
00036 #ifndef ARP_TICK_INTERVAL
00037    #define ARP_TICK_INTERVAL 200
00038 #elif (ARP_TICK_INTERVAL < 10)
00039    #error ARP_TICK_INTERVAL parameter is not valid
00040 #endif
00041 
00042 //Size of ARP cache
00043 #ifndef ARP_CACHE_SIZE
00044    #define ARP_CACHE_SIZE 8
00045 #elif (ARP_CACHE_SIZE < 4)
00046    #error ARP_CACHE_SIZE parameter is not valid
00047 #endif
00048 
00049 //Maximum number of packets waiting for address resolution to complete
00050 #ifndef ARP_MAX_PENDING_PACKETS
00051    #define ARP_MAX_PENDING_PACKETS 2
00052 #elif (ARP_MAX_PENDING_PACKETS < 1)
00053    #error ARP_MAX_PENDING_PACKETS parameter is not valid
00054 #endif
00055 
00056 //Maximum number of times that an ARP request will be retransmitted
00057 #ifndef ARP_MAX_REQUESTS
00058    #define ARP_MAX_REQUESTS 3
00059 #elif (ARP_MAX_REQUESTS < 1)
00060    #error ARP_MAX_REQUESTS parameter is not valid
00061 #endif
00062 
00063 //Time interval between subsequent retransmissions of ARP requests
00064 #ifndef ARP_REQUEST_TIMEOUT
00065    #define ARP_REQUEST_TIMEOUT 1000
00066 #elif (ARP_REQUEST_TIMEOUT < 100)
00067    #error ARP_REQUEST_TIMEOUT parameter is not valid
00068 #endif
00069 
00070 //Maximum number of times that a probe will be retransmitted
00071 #ifndef ARP_MAX_PROBES
00072    #define ARP_MAX_PROBES 2
00073 #elif (ARP_MAX_PROBES < 1)
00074    #error ARP_MAX_PROBES parameter is not valid
00075 #endif
00076 
00077 //time interval between subsequent retransmissions of probes
00078 #ifndef ARP_PROBE_TIMEOUT
00079    #define ARP_PROBE_TIMEOUT 60000
00080 #elif (ARP_PROBE_TIMEOUT < 1000)
00081    #error ARP_PROBE_TIMEOUT parameter is not valid
00082 #endif
00083 
00084 //The time a host is considered reachable after receiving a reachability confirmation
00085 #ifndef ARP_REACHABLE_TIME
00086    #define ARP_REACHABLE_TIME 60000
00087 #elif (ARP_REACHABLE_TIME < 1000)
00088    #error ARP_REACHABLE_TIME parameter is not valid
00089 #endif
00090 
00091 //Delay before sending the first probe
00092 #ifndef ARP_DELAY_FIRST_PROBE_TIME
00093    #define ARP_DELAY_FIRST_PROBE_TIME 5000
00094 #elif (ARP_DELAY_FIRST_PROBE_TIME < 1000)
00095    #error ARP_DELAY_FIRST_PROBE_TIME parameter is not valid
00096 #endif
00097 
00098 //Hardware type
00099 #define ARP_HARDWARE_TYPE_ETH 0x0001
00100 //Protocol type
00101 #define ARP_PROTOCOL_TYPE_IPV4 0x0800
00102 
00103 
00104 /**
00105  * @brief ARP opcodes
00106  **/
00107 
00108 typedef enum
00109 {
00110    ARP_OPCODE_ARP_REQUEST = 1,
00111    ARP_OPCODE_ARP_REPLY   = 2
00112 } ArpOpcode;
00113 
00114 
00115 /**
00116  * @brief ARP cache entry states
00117  **/
00118 
00119 typedef enum
00120 {
00121    ARP_STATE_NONE       = 0,
00122    ARP_STATE_INCOMPLETE = 1,
00123    ARP_STATE_REACHABLE  = 2,
00124    ARP_STATE_STALE      = 3,
00125    ARP_STATE_DELAY      = 4,
00126    ARP_STATE_PROBE      = 5,
00127    ARP_STATE_PERMANENT  = 6
00128 } ArpState;
00129 
00130 
00131 //CodeWarrior or Win32 compiler?
00132 #if defined(__CWCC__) || defined(_WIN32)
00133    #pragma pack(push, 1)
00134 #endif
00135 
00136 
00137 /**
00138  * @brief ARP packet
00139  **/
00140 
00141 typedef __start_packed struct
00142 {
00143    uint16_t hrd; //0-1
00144    uint16_t pro; //2-3
00145    uint8_t hln;  //4
00146    uint8_t pln;  //5
00147    uint16_t op;  //6-7
00148    MacAddr sha;  //8-13
00149    Ipv4Addr spa; //14-17
00150    MacAddr tha;  //18-23
00151    Ipv4Addr tpa; //24-27
00152 } __end_packed ArpPacket;
00153 
00154 
00155 //CodeWarrior or Win32 compiler?
00156 #if defined(__CWCC__) || defined(_WIN32)
00157    #pragma pack(pop)
00158 #endif
00159 
00160 
00161 /**
00162  * @brief ARP queue item
00163  **/
00164 
00165 typedef struct
00166 {
00167    NetBuffer *buffer; //Packet waiting for address resolution
00168    size_t offset;         //Offset to the first byte of the packet
00169 } ArpQueueItem;
00170 
00171 
00172 /**
00173  * @brief ARP cache entry
00174  **/
00175 
00176 typedef struct
00177 {
00178    ArpState state;                              //Reachability state
00179    Ipv4Addr ipAddr;                             //Unicast IPv4 address
00180    MacAddr macAddr;                             //Link layer address associated with the IPv4 address
00181    systime_t timestamp;                         //Time stamp to manage entry lifetime
00182    systime_t timeout;                           //Timeout value
00183    uint_t retransmitCount;                      //Retransmission counter
00184    ArpQueueItem queue[ARP_MAX_PENDING_PACKETS]; //Packets waiting for address resolution to complete
00185    uint_t queueSize;                            //Number of queued packets
00186 } ArpCacheEntry;
00187 
00188 
00189 //Tick counter to handle periodic operations
00190 extern systime_t arpTickCounter;
00191 
00192 //ARP related functions
00193 error_t arpInit(NetInterface *interface);
00194 void arpFlushCache(NetInterface *interface);
00195 
00196 ArpCacheEntry *arpCreateEntry(NetInterface *interface);
00197 ArpCacheEntry *arpFindEntry(NetInterface *interface, Ipv4Addr ipAddr);
00198 
00199 void arpSendQueuedPackets(NetInterface *interface, ArpCacheEntry *entry);
00200 void arpFlushQueuedPackets(NetInterface *interface, ArpCacheEntry *entry);
00201 
00202 error_t arpResolve(NetInterface *interface, Ipv4Addr ipAddr, MacAddr *macAddr);
00203 
00204 error_t arpEnqueuePacket(NetInterface *interface,
00205    Ipv4Addr ipAddr, NetBuffer *buffer, size_t offset);
00206 
00207 void arpTick(NetInterface *interface);
00208 
00209 void arpProcessPacket(NetInterface *interface, ArpPacket *arpPacket, size_t length);
00210 void arpProcessRequest(NetInterface *interface, ArpPacket *arpRequest);
00211 void arpProcessReply(NetInterface *interface, ArpPacket *arpResponse);
00212 
00213 error_t arpSendProbe(NetInterface *interface, Ipv4Addr targetIpAddr);
00214 
00215 error_t arpSendRequest(NetInterface *interface,
00216    Ipv4Addr targetIpAddr, const MacAddr *destMacAddr);
00217 
00218 error_t arpSendReply(NetInterface *interface, Ipv4Addr targetIpAddr,
00219    const MacAddr *targetMacAddr, const MacAddr *destMacAddr);
00220 
00221 void arpDumpPacket(const ArpPacket *arpPacket);
00222 
00223 #endif
00224