xref: /minix/usr.sbin/traceroute/ifaddrlist.c (revision 00b67f09)
1 /*	$NetBSD: ifaddrlist.c,v 1.10 2011/09/11 01:06:26 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997, 1998, 1999, 2000
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the Computer Systems
18  *	Engineering Group at Lawrence Berkeley Laboratory.
19  * 4. Neither the name of the University nor of the Laboratory may be used
20  *    to endorse or promote products derived from this software without
21  *    specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static const char rcsid[] =
40     "@(#) Header: ifaddrlist.c,v 1.2 97/04/22 13:31:05 leres Exp  (LBL)";
41     "@(#) Id: ifaddrlist.c,v 1.9 2000/11/23 20:01:55 leres Exp  (LBL)";
42 #else
43 __RCSID("$NetBSD: ifaddrlist.c,v 1.10 2011/09/11 01:06:26 christos Exp $");
44 #endif
45 #endif
46 
47 #include <sys/param.h>
48 #include <sys/file.h>
49 #include <sys/ioctl.h>
50 #include <sys/socket.h>
51 #ifdef HAVE_SYS_SOCKIO_H
52 #include <sys/sockio.h>
53 #endif
54 #include <sys/time.h>				/* concession to AIX */
55 
56 struct mbuf;
57 struct rtentry;
58 
59 #include <net/if.h>
60 #include <netinet/in.h>
61 #include <arpa/inet.h>
62 
63 #include <ctype.h>
64 #include <errno.h>
65 #include <memory.h>
66 #include <stdio.h>
67 #include <stdlib.h>
68 #include <string.h>
69 #include <unistd.h>
70 #include <ifaddrs.h>
71 
72 #include "gnuc.h"
73 #ifdef HAVE_OS_PROTO_H
74 #include "os-proto.h"
75 #endif
76 
77 #include "ifaddrlist.h"
78 
79 /* Not all systems have IFF_LOOPBACK */
80 #ifdef IFF_LOOPBACK
81 #define ISLOOPBACK(p) ((p)->ifa_flags & IFF_LOOPBACK)
82 #else
83 #define ISLOOPBACK(p) (strcmp((p)->ifa_name, "lo0") == 0)
84 #endif
85 
86 /*
87  * Return the interface list
88  */
89 ssize_t
90 ifaddrlist(struct ifaddrlist **ipaddrp, char *errbuf, size_t buflen)
91 {
92 	struct sockaddr_in *sin;
93 	struct ifaddrs *ifap = NULL, *ifa;
94 	struct ifaddrlist *al = NULL, *nal;
95 	size_t i = 0, maxal = 10;
96 
97 	if (getifaddrs(&ifap) != 0)
98 		goto out;
99 
100 	if ((al = malloc(maxal * sizeof(*al))) == NULL)
101 		goto out;
102 
103 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
104 		if (ifa->ifa_addr->sa_family != AF_INET)
105 			continue;
106 
107 		/* Must be up */
108 		if ((ifa->ifa_flags & IFF_UP) == 0)
109 			continue;
110 
111 		/*
112 		 * Must not be a loopback address (127/8)
113 		 */
114 		sin = (struct sockaddr_in *)ifa->ifa_addr;
115 		if (ISLOOPBACK(ifa))
116 			if (ntohl(sin->sin_addr.s_addr) == INADDR_LOOPBACK)
117 				continue;
118 
119 		if (i == maxal) {
120 			maxal <<= 1;
121 			if ((nal = realloc(al, maxal * sizeof(*al))) == NULL)
122 				goto out;
123 			al = nal;
124 		}
125 
126 		al[i].addr = sin->sin_addr.s_addr;
127 		if ((al[i].device = strdup(ifa->ifa_name)) == NULL)
128 			goto out;
129 		i++;
130 	}
131 	if ((nal = realloc(al, i * sizeof(*al))) == NULL)
132 		goto out;
133 	freeifaddrs(ifap);
134 	*ipaddrp = nal;
135 	return (ssize_t)i;
136 out:
137 	if (ifap)
138 		freeifaddrs(ifap);
139 	if (al) {
140 		while (i > 0)
141 			free(al[--i].device);
142 		free(al);
143 	}
144 	(void)snprintf(errbuf, buflen, "%s: %s", __func__, strerror(errno));
145 	return -1;
146 }
147