xref: /titanic_41/usr/src/lib/libinetutil/common/inetutil.c (revision 9e86db79b7d1bbc5f2f04e99954cbd5eae0e22bb)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <unistd.h>
28 #include <netinet/in.h>
29 #include <libinetutil.h>
30 
31 extern int getnetmaskbyaddr(const struct in_addr, struct in_addr *);
32 
33 /*
34  * Internet utility functions.
35  */
36 
37 /*
38  * Given a host-order address, calculate client's default net mask.
39  * Consult netmasks database to see if net is further subnetted.
40  * We'll only snag the first netmask that matches our criteria.
41  * We return the resultant netmask in host order.
42  */
43 void
44 get_netmask4(const struct in_addr *n_addrp, struct in_addr *s_addrp)
45 {
46 	struct in_addr	hp, tp;
47 
48 	/*
49 	 * First check if VLSM is in use.
50 	 */
51 	hp.s_addr = htonl(n_addrp->s_addr);
52 	if (getnetmaskbyaddr(hp, &tp) == 0) {
53 		s_addrp->s_addr = ntohl(tp.s_addr);
54 		return;
55 	}
56 
57 	/*
58 	 * Fall back on standard classed networks.
59 	 */
60 	if (IN_CLASSA(n_addrp->s_addr))
61 		s_addrp->s_addr = IN_CLASSA_NET;
62 	else if (IN_CLASSB(n_addrp->s_addr))
63 		s_addrp->s_addr = IN_CLASSB_NET;
64 	else if (IN_CLASSC(n_addrp->s_addr))
65 		s_addrp->s_addr = IN_CLASSC_NET;
66 	else
67 		s_addrp->s_addr = IN_CLASSE_NET;
68 }
69 
70 /*
71  * Checks if the IP addresses `ssp1' and `ssp2' are equal.
72  */
73 boolean_t
74 sockaddrcmp(const struct sockaddr_storage *ssp1,
75     const struct sockaddr_storage *ssp2)
76 {
77 	struct in_addr addr1, addr2;
78 	const struct in6_addr *addr6p1, *addr6p2;
79 
80 	if (ssp1->ss_family != ssp2->ss_family)
81 		return (B_FALSE);
82 
83 	if (ssp1 == ssp2)
84 		return (B_TRUE);
85 
86 	switch (ssp1->ss_family) {
87 	case AF_INET:
88 		addr1 = ((const struct sockaddr_in *)ssp1)->sin_addr;
89 		addr2 = ((const struct sockaddr_in *)ssp2)->sin_addr;
90 		return (addr1.s_addr == addr2.s_addr);
91 	case AF_INET6:
92 		addr6p1 = &((const struct sockaddr_in6 *)ssp1)->sin6_addr;
93 		addr6p2 = &((const struct sockaddr_in6 *)ssp2)->sin6_addr;
94 		return (IN6_ARE_ADDR_EQUAL(addr6p1, addr6p2));
95 	}
96 	return (B_FALSE);
97 }
98