1 /* $NetBSD: ifaddrlist.c,v 1.12 2021/10/30 09:26:11 nia 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 1.12 2021/10/30 09:26:11 nia 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 #include "prog_ops.h"
79
80 /* Not all systems have IFF_LOOPBACK */
81 #ifdef IFF_LOOPBACK
82 #define ISLOOPBACK(p) ((p)->ifa_flags & IFF_LOOPBACK)
83 #else
84 #define ISLOOPBACK(p) (strcmp((p)->ifa_name, "lo0") == 0)
85 #endif
86
87 /*
88 * Return the interface list
89 */
90 ssize_t
ifaddrlist(struct ifaddrlist ** ipaddrp,char * errbuf,size_t buflen)91 ifaddrlist(struct ifaddrlist **ipaddrp, char *errbuf, size_t buflen)
92 {
93 struct sockaddr_in *sin;
94 struct ifaddrs *ifap = NULL, *ifa;
95 struct ifaddrlist *al = NULL;
96 size_t i = 0, maxal = 10;
97
98 if (prog_getifaddrs(&ifap) != 0)
99 goto out;
100
101 if (reallocarr(&al, maxal, sizeof(*al)) != 0)
102 goto out;
103
104 for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
105 if (ifa->ifa_addr->sa_family != AF_INET)
106 continue;
107
108 /* Must be up */
109 if ((ifa->ifa_flags & IFF_UP) == 0)
110 continue;
111
112 /*
113 * Must not be a loopback address (127/8)
114 */
115 sin = (struct sockaddr_in *)ifa->ifa_addr;
116 if (ISLOOPBACK(ifa))
117 if (ntohl(sin->sin_addr.s_addr) == INADDR_LOOPBACK)
118 continue;
119
120 if (i == maxal) {
121 maxal <<= 1;
122 if (reallocarr(&al, maxal, sizeof(*al)) != 0)
123 goto out;
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 (reallocarr(&al, i, sizeof(*al)) != 0)
132 goto out;
133 freeifaddrs(ifap);
134 *ipaddrp = al;
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