1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 1983 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include <sys/types.h> 30 #include <netinet/in.h> 31 32 /* 33 * Return the network number from an internet 34 * address; handles class a/b/c network #'s. 35 */ 36 int 37 inet_netof(struct in_addr in) 38 { 39 u_long i = ntohl(in.s_addr); 40 41 if (IN_CLASSA(i)) 42 return (((i)&IN_CLASSA_NET) >> IN_CLASSA_NSHIFT); 43 else if (IN_CLASSB(i)) 44 return (((i)&IN_CLASSB_NET) >> IN_CLASSB_NSHIFT); 45 else 46 return (((i)&IN_CLASSC_NET) >> IN_CLASSC_NSHIFT); 47 } 48