xref: /illumos-gate/usr/src/lib/libinetutil/common/ifaddrlistx.c (revision 0250c53ad267726f2438e3c6556199a0bbf588a2)
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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
22  * Use is subject to license terms.
23  */
24 
25 #include <errno.h>
26 #include <libinetutil.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <unistd.h>
31 #include <sys/socket.h>
32 #include <sys/sockio.h>
33 
34 /*
35  * Create a list of the addresses on physical interface `ifname' with at least
36  * one of the flags in `set' set and all of the flags in `clear' clear.
37  * Return the number of items in the list, or -1 on failure.
38  */
39 int
40 ifaddrlistx(const char *ifname, uint64_t set, uint64_t clear,
41     ifaddrlistx_t **ifaddrsp)
42 {
43 	struct lifconf	lifc;
44 	struct lifnum	lifn;
45 	struct lifreq	*lifrp;
46 	ifaddrlistx_t	*ifaddrp, *ifaddrs = NULL;
47 	int		i, nlifr, naddr = 0;
48 	char		*cp;
49 	uint_t		flags;
50 	int		s4, s6 = -1;
51 	boolean_t	isv6;
52 	int		save_errno;
53 	struct sockaddr_storage addr;
54 
55 	(void) memset(&lifc, 0, sizeof (lifc));
56 	flags = LIFC_NOXMIT | LIFC_ALLZONES | LIFC_TEMPORARY | LIFC_UNDER_IPMP;
57 
58 	/*
59 	 * We need both IPv4 and IPv6 sockets to query both IPv4 and IPv6
60 	 * interfaces below.
61 	 */
62 	if ((s4 = socket(AF_INET, SOCK_DGRAM, 0)) == -1 ||
63 	    (s6 = socket(AF_INET6, SOCK_DGRAM, 0)) == -1) {
64 		goto fail;
65 	}
66 
67 	/*
68 	 * Get the number of network interfaces of type `family'.
69 	 */
70 	lifn.lifn_family = AF_UNSPEC;
71 	lifn.lifn_flags = flags;
72 again:
73 	if (ioctl(s4, SIOCGLIFNUM, &lifn) == -1)
74 		goto fail;
75 
76 	/*
77 	 * Pad the interface count to detect when additional interfaces have
78 	 * been configured between SIOCGLIFNUM and SIOCGLIFCONF.
79 	 */
80 	lifn.lifn_count += 4;
81 
82 	lifc.lifc_flags = flags;
83 	lifc.lifc_family = AF_UNSPEC;
84 	lifc.lifc_len = lifn.lifn_count * sizeof (struct lifreq);
85 	if ((lifc.lifc_buf = realloc(lifc.lifc_buf, lifc.lifc_len)) == NULL)
86 		goto fail;
87 
88 	if (ioctl(s4, SIOCGLIFCONF, &lifc) == -1)
89 		goto fail;
90 
91 	/*
92 	 * If every lifr_req slot is taken, then additional interfaces must
93 	 * have been plumbed between the SIOCGLIFNUM and the SIOCGLIFCONF.
94 	 * Recalculate to make sure we didn't miss any interfaces.
95 	 */
96 	nlifr = lifc.lifc_len / sizeof (struct lifreq);
97 	if (nlifr >= lifn.lifn_count)
98 		goto again;
99 
100 	/*
101 	 * Populate the ifaddrlistx by querying each matching interface.  If a
102 	 * query ioctl returns ENXIO, then the interface must have been
103 	 * removed after the SIOCGLIFCONF completed -- so we just ignore it.
104 	 */
105 	for (lifrp = lifc.lifc_req, i = 0; i < nlifr; i++, lifrp++) {
106 		if ((cp = strchr(lifrp->lifr_name, ':')) != NULL)
107 			*cp = '\0';
108 
109 		if (strcmp(lifrp->lifr_name, ifname) != 0)
110 			continue;
111 
112 		if (cp != NULL)
113 			*cp = ':';
114 
115 		addr = lifrp->lifr_addr;
116 		isv6 = addr.ss_family == AF_INET6;
117 		if (ioctl(isv6 ? s6 : s4, SIOCGLIFFLAGS, lifrp) == -1) {
118 			if (errno == ENXIO)
119 				continue;
120 			goto fail;
121 		}
122 
123 		if (set != 0 && ((lifrp->lifr_flags & set) == 0) ||
124 		    (lifrp->lifr_flags & clear) != 0)
125 			continue;
126 
127 		/*
128 		 * We've got a match; allocate a new record.
129 		 */
130 		if ((ifaddrp = malloc(sizeof (ifaddrlistx_t))) == NULL)
131 			goto fail;
132 
133 		(void) strlcpy(ifaddrp->ia_name, lifrp->lifr_name, LIFNAMSIZ);
134 		ifaddrp->ia_flags = lifrp->lifr_flags;
135 		ifaddrp->ia_addr = addr;
136 		ifaddrp->ia_next = ifaddrs;
137 		ifaddrs = ifaddrp;
138 		naddr++;
139 	}
140 
141 	(void) close(s4);
142 	(void) close(s6);
143 	free(lifc.lifc_buf);
144 	*ifaddrsp = ifaddrs;
145 	return (naddr);
146 fail:
147 	save_errno = errno;
148 	(void) close(s4);
149 	(void) close(s6);
150 	free(lifc.lifc_buf);
151 	ifaddrlistx_free(ifaddrs);
152 	errno = save_errno;
153 	return (-1);
154 }
155 
156 /*
157  * Free the provided ifaddrlistx_t.
158  */
159 void
160 ifaddrlistx_free(ifaddrlistx_t *ifaddrp)
161 {
162 	ifaddrlistx_t *next_ifaddrp;
163 
164 	for (; ifaddrp != NULL; ifaddrp = next_ifaddrp) {
165 		next_ifaddrp = ifaddrp->ia_next;
166 		free(ifaddrp);
167 	}
168 }
169