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
subnet_number(struct iaddr addr,struct iaddr mask)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
broadcast_addr(struct iaddr subnet,struct iaddr mask)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
addr_eq(struct iaddr addr1,struct iaddr addr2)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 *
piaddr(struct iaddr addr)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