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, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 #pragma ident "%Z%%M% %I% %E% SMI"
23
24 /*
25 * get_myaddress.c
26 *
27 * Get client's IP address via ioctl. This avoids using the NIS.
28 * Copyright (C) 1990, Sun Microsystems, Inc.
29 */
30
31 #include <rpc/types.h>
32 #include <rpc/pmap_prot.h>
33 #include <sys/socket.h>
34 #include <sys/sockio.h>
35 #include <stdio.h>
36 #include <net/if.h>
37 #include <sys/ioctl.h>
38 #include <arpa/inet.h>
39 #include <netinet/in.h>
40 #include <syslog.h>
41 #include <malloc.h>
42 #include <unistd.h>
43 #include <stropts.h>
44 #include <stdlib.h>
45 #include <errno.h>
46
47 /*
48 * don't use gethostbyname, which would invoke NIS
49 */
50 void
get_myaddress(struct sockaddr_in * addr)51 get_myaddress(struct sockaddr_in *addr)
52 {
53 int s;
54 struct ifconf ifc;
55 struct ifreq ifreq, *ifr;
56 int len, numifs;
57 int ret;
58
59 if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
60 syslog(LOG_ERR, "get_myaddress: socket: %m");
61 exit(1);
62 }
63
64 do {
65 ret = ioctl(s, SIOCGIFNUM, (char *)&numifs);
66 } while (ret < 0 && (errno == EINTR || errno == EAGAIN));
67 if (ret < 0) {
68 syslog(LOG_ERR, "get_myaddress: ioctl: %m");
69 exit(1);
70 }
71
72 ifc.ifc_len = numifs * sizeof (struct ifreq);
73 if ((ifc.ifc_buf = (caddr_t)malloc(ifc.ifc_len)) == NULL) {
74 syslog(LOG_ERR, "get_myaddress: malloc: %m");
75 exit(1);
76 }
77
78 do {
79 ret = ioctl(s, SIOCGIFCONF, (char *)&ifc);
80 } while (ret < 0 && (errno == EINTR || errno == EAGAIN));
81 if (ret < 0) {
82 syslog(LOG_ERR,
83 "get_myaddress: ioctl (get interface configuration): %m");
84 exit(1);
85 }
86
87 /*
88 * set default to loopback in case nothing is found.
89 */
90 addr->sin_family = AF_INET;
91 addr->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
92 addr->sin_port = htons(PMAPPORT);
93
94 ifr = ifc.ifc_req;
95 for (len = ifc.ifc_len; len > 0; len -= sizeof (ifreq), ifr++) {
96 ifreq = *ifr;
97 do {
98 ret = ioctl(s, SIOCGIFFLAGS, (char *)&ifreq);
99 } while (ret < 0 && (errno == EINTR || errno == EAGAIN));
100 if (ret < 0) {
101 syslog(LOG_ERR, "get_myaddress: ioctl: %m");
102 exit(1);
103 }
104 if (ifr->ifr_addr.sa_family != AF_INET)
105 continue;
106 if ((ifreq.ifr_flags & IFF_UP) == 0)
107 continue;
108 if (ifreq.ifr_flags & IFF_LOOPBACK)
109 continue;
110 if ((ifreq.ifr_flags & (IFF_MULTICAST | IFF_BROADCAST)) == 0)
111 continue;
112 *addr = *((struct sockaddr_in *)&ifr->ifr_addr);
113 addr->sin_port = htons(PMAPPORT);
114 break;
115 }
116 free(ifc.ifc_buf);
117 (void) close(s);
118 }
119