arp.h

00001 #ifndef ARP_H
00002 #define ARP_H
00003 
00004 #include "net.h"
00005 
00006 /**
00007   \file
00008   \brief ARP packet
00009   
00010   This file contains the memory map and associated functions for ARP packet
00011   creation and deconstruction. 
00012 */
00013 
00014 #define ETHERTYPE_ARP 0x0806
00015 
00016 /// ARP Packet memory map
00017 typedef struct {
00018   u16 hardware_type; ///< 0x0001 for ethernet
00019   u16 protocol_type; ///< 0x0800 for IPv4
00020   u8  hardware_length; ///< Bytes.  Ethernet is 6
00021   u8  protocol_length; ///< Bytes.  IPv4 is 4
00022   u16 operation; ///< Operation.  1 for request, 2 for reply or announce
00023   // The following are only valid for IPv4 over Ethernet
00024   u8  sender_hardware_address[6]; ///< Generator of the request or reply
00025   u8  sender_protocol_address[4]; ///< All zeroes for an ARP probe
00026   u8  target_hardware_address[6]; ///< Announce - same as SHA
00027   u8  target_protocol_address[4]; ///< Announce - Same as TPA
00028 } ARP_Packet;
00029 
00030 /// Convert from wire to host or host to wire endianness
00031 inline void fix_endian_arp(ARP_Packet *packet)
00032 {
00033   fix_endian_u16(&packet->hardware_type);
00034   fix_endian_u16(&packet->protocol_type);
00035   fix_endian_u16(&packet->operation);
00036 }
00037 
00038 /// Print the ARP packet
00039 inline void print_arp(ARP_Packet *packet)
00040 {
00041     main_log.printf("ARP Packet:");
00042     main_log.printf("  Hardware:  0x%04X", packet->hardware_type);
00043     main_log.printf("  Protocol:  0x%04X", packet->protocol_type);
00044     main_log.printf("  Type:      %d", packet->operation);
00045     if (packet->hardware_type != 0x0001 || packet->protocol_type != 0x0800) return;
00046     
00047     u8 *bytes;
00048     bytes = packet->sender_hardware_address;
00049     main_log.printf("  Source:    MAC - %02X:%02X:%02X:%02X:%02X:%02X", bytes[0],bytes[1],bytes[2],bytes[3],bytes[4],bytes[5]);
00050     bytes = packet->target_hardware_address;
00051     main_log.printf("  Target:    MAC - %02X:%02X:%02X:%02X:%02X:%02X", bytes[0],bytes[1],bytes[2],bytes[3],bytes[4],bytes[5]);
00052     bytes = packet->sender_protocol_address;
00053     main_log.printf("  Source:    IP  - %03d.%03d.%03d.%03d", bytes[0], bytes[1], bytes[2], bytes[3]);
00054     bytes = packet->target_protocol_address;
00055     main_log.printf("  Target:    IP  - %03d.%03d.%03d.%03d", bytes[0], bytes[1], bytes[2], bytes[3]);
00056 }
00057 
00058 #endif