xref: /freebsd/sbin/ifconfig/ifclone.c (revision eb69d1f144a6fcc765d1b9d44a5ae8082353e70b)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 static const char rcsid[] =
34   "$FreeBSD$";
35 #endif /* not lint */
36 
37 #include <sys/param.h>
38 #include <sys/ioctl.h>
39 #include <sys/queue.h>
40 #include <sys/socket.h>
41 #include <net/if.h>
42 
43 #include <err.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 #include "ifconfig.h"
50 
51 static void
52 list_cloners(void)
53 {
54 	struct if_clonereq ifcr;
55 	char *cp, *buf;
56 	int idx;
57 	int s;
58 
59 	s = socket(AF_LOCAL, SOCK_DGRAM, 0);
60 	if (s == -1)
61 		err(1, "socket(AF_LOCAL,SOCK_DGRAM)");
62 
63 	memset(&ifcr, 0, sizeof(ifcr));
64 
65 	if (ioctl(s, SIOCIFGCLONERS, &ifcr) < 0)
66 		err(1, "SIOCIFGCLONERS for count");
67 
68 	buf = malloc(ifcr.ifcr_total * IFNAMSIZ);
69 	if (buf == NULL)
70 		err(1, "unable to allocate cloner name buffer");
71 
72 	ifcr.ifcr_count = ifcr.ifcr_total;
73 	ifcr.ifcr_buffer = buf;
74 
75 	if (ioctl(s, SIOCIFGCLONERS, &ifcr) < 0)
76 		err(1, "SIOCIFGCLONERS for names");
77 
78 	/*
79 	 * In case some disappeared in the mean time, clamp it down.
80 	 */
81 	if (ifcr.ifcr_count > ifcr.ifcr_total)
82 		ifcr.ifcr_count = ifcr.ifcr_total;
83 
84 	for (cp = buf, idx = 0; idx < ifcr.ifcr_count; idx++, cp += IFNAMSIZ) {
85 		if (idx > 0)
86 			putchar(' ');
87 		printf("%s", cp);
88 	}
89 
90 	putchar('\n');
91 	free(buf);
92 	close(s);
93 }
94 
95 struct clone_defcb {
96 	char ifprefix[IFNAMSIZ];
97 	clone_callback_func *clone_cb;
98 	SLIST_ENTRY(clone_defcb) next;
99 };
100 
101 static SLIST_HEAD(, clone_defcb) clone_defcbh =
102    SLIST_HEAD_INITIALIZER(clone_defcbh);
103 
104 void
105 clone_setdefcallback(const char *ifprefix, clone_callback_func *p)
106 {
107 	struct clone_defcb *dcp;
108 
109 	dcp = malloc(sizeof(*dcp));
110 	strlcpy(dcp->ifprefix, ifprefix, IFNAMSIZ-1);
111 	dcp->clone_cb = p;
112 	SLIST_INSERT_HEAD(&clone_defcbh, dcp, next);
113 }
114 
115 /*
116  * Do the actual clone operation.  Any parameters must have been
117  * setup by now.  If a callback has been setup to do the work
118  * then defer to it; otherwise do a simple create operation with
119  * no parameters.
120  */
121 static void
122 ifclonecreate(int s, void *arg)
123 {
124 	struct ifreq ifr;
125 	struct clone_defcb *dcp;
126 	clone_callback_func *clone_cb = NULL;
127 
128 	memset(&ifr, 0, sizeof(ifr));
129 	(void) strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
130 
131 	if (clone_cb == NULL) {
132 		/* Try to find a default callback */
133 		SLIST_FOREACH(dcp, &clone_defcbh, next) {
134 			if (strncmp(dcp->ifprefix, ifr.ifr_name,
135 			    strlen(dcp->ifprefix)) == 0) {
136 				clone_cb = dcp->clone_cb;
137 				break;
138 			}
139 		}
140 	}
141 	if (clone_cb == NULL) {
142 		/* NB: no parameters */
143 		if (ioctl(s, SIOCIFCREATE2, &ifr) < 0)
144 			err(1, "SIOCIFCREATE2");
145 	} else {
146 		clone_cb(s, &ifr);
147 	}
148 
149 	/*
150 	 * If we get a different name back than we put in, update record and
151 	 * indicate it should be printed later.
152 	 */
153 	if (strncmp(name, ifr.ifr_name, sizeof(name)) != 0) {
154 		strlcpy(name, ifr.ifr_name, sizeof(name));
155 		printifname = 1;
156 	}
157 }
158 
159 static
160 DECL_CMD_FUNC(clone_create, arg, d)
161 {
162 	callback_register(ifclonecreate, NULL);
163 }
164 
165 static
166 DECL_CMD_FUNC(clone_destroy, arg, d)
167 {
168 	(void) strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
169 	if (ioctl(s, SIOCIFDESTROY, &ifr) < 0)
170 		err(1, "SIOCIFDESTROY");
171 }
172 
173 static struct cmd clone_cmds[] = {
174 	DEF_CLONE_CMD("create",	0,	clone_create),
175 	DEF_CMD("destroy",	0,	clone_destroy),
176 	DEF_CLONE_CMD("plumb",	0,	clone_create),
177 	DEF_CMD("unplumb",	0,	clone_destroy),
178 };
179 
180 static void
181 clone_Copt_cb(const char *optarg __unused)
182 {
183 	list_cloners();
184 	exit(0);
185 }
186 static struct option clone_Copt = { .opt = "C", .opt_usage = "[-C]", .cb = clone_Copt_cb };
187 
188 static __constructor void
189 clone_ctor(void)
190 {
191 	size_t i;
192 
193 	for (i = 0; i < nitems(clone_cmds);  i++)
194 		cmd_register(&clone_cmds[i]);
195 	opt_register(&clone_Copt);
196 }
197