1 /* 2 * Copyright (c) 1982, 1986 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 * 17 * @(#)if_en.h 7.2 (Berkeley) 08/04/88 18 */ 19 20 /* 21 * Structure of a Ethernet header. 22 */ 23 struct en_header { 24 u_char en_shost; 25 u_char en_dhost; 26 u_short en_type; 27 }; 28 29 #define ENTYPE_PUP 0x0200 /* PUP protocol */ 30 #define ENTYPE_IP 0x0201 /* IP protocol */ 31 32 /* 33 * The ENTYPE_NTRAILER packet types starting at 34 * ENTYPE_TRAIL have (type-ENTYPE_TRAIL)*512 bytes 35 * of data followed by an Ethernet type (as given above) 36 * and then the (variable-length) header. 37 */ 38 #define ENTYPE_TRAIL 0x1000 /* Trailer type */ 39 #define ENTYPE_NTRAILER 16 40 41 #define EN_BROADCAST 0 /* Hardware broadcast address */ 42