1 /* $OpenBSD: inet.c,v 1.7 2004/05/04 21:48:16 deraadt Exp $ */ 2 /* $DragonFly: src/sbin/dhclient/inet.c,v 1.1 2008/08/30 16:07:58 hasso Exp $ */ 3 4 /* 5 * Subroutines to manipulate internet addresses in a safely portable 6 * way... 7 */ 8 9 /* 10 * Copyright (c) 1996 The Internet Software Consortium. All rights reserved. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of The Internet Software Consortium nor the names 22 * of its contributors may be used to endorse or promote products derived 23 * from this software without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND 26 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 27 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 28 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 29 * DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR 30 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 31 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 32 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 33 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 34 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 35 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 36 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * This software has been written for the Internet Software Consortium 40 * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie 41 * Enterprises. To learn more about the Internet Software Consortium, 42 * see ``http://www.vix.com/isc''. To learn more about Vixie 43 * Enterprises, see ``http://www.vix.com''. 44 */ 45 46 #include "dhcpd.h" 47 48 /* 49 * Return just the network number of an internet address... 50 */ 51 struct iaddr 52 subnet_number(struct iaddr addr, struct iaddr mask) 53 { 54 struct iaddr rv; 55 int i; 56 57 rv.len = 0; 58 59 /* Both addresses must have the same length... */ 60 if (addr.len != mask.len) 61 return (rv); 62 63 rv.len = addr.len; 64 for (i = 0; i < rv.len; i++) 65 rv.iabuf[i] = addr.iabuf[i] & mask.iabuf[i]; 66 return (rv); 67 } 68 69 /* 70 * Given a subnet number and netmask, return the address on that subnet 71 * for which the host portion of the address is all ones (the standard 72 * broadcast address). 73 */ 74 struct iaddr 75 broadcast_addr(struct iaddr subnet, struct iaddr mask) 76 { 77 struct iaddr rv; 78 int i; 79 80 if (subnet.len != mask.len) { 81 rv.len = 0; 82 return (rv); 83 } 84 85 for (i = 0; i < subnet.len; i++) 86 rv.iabuf[i] = subnet.iabuf[i] | (~mask.iabuf[i] & 255); 87 rv.len = subnet.len; 88 89 return (rv); 90 } 91 92 int 93 addr_eq(struct iaddr addr1, struct iaddr addr2) 94 { 95 if (addr1.len != addr2.len) 96 return (0); 97 return (memcmp(addr1.iabuf, addr2.iabuf, addr1.len) == 0); 98 } 99 100 char * 101 piaddr(struct iaddr addr) 102 { 103 static char pbuf[32]; 104 struct in_addr a; 105 char *s; 106 107 memcpy(&a, &(addr.iabuf), sizeof(struct in_addr)); 108 109 if (addr.len == 0) 110 strlcpy(pbuf, "<null address>", sizeof(pbuf)); 111 else { 112 s = inet_ntoa(a); 113 if (s != NULL) 114 strlcpy(pbuf, s, sizeof(pbuf)); 115 else 116 strlcpy(pbuf, "<invalid address>", sizeof(pbuf)); 117 } 118 return (pbuf); 119 } 120