xref: /freebsd/sbin/ifconfig/ifclone.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifndef lint
31 static const char rcsid[] =
32   "$FreeBSD$";
33 #endif /* not lint */
34 
35 #include <sys/queue.h>
36 #include <sys/types.h>
37 #include <sys/ioctl.h>
38 #include <sys/socket.h>
39 #include <net/if.h>
40 
41 #include <err.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <unistd.h>
46 
47 #include "ifconfig.h"
48 
49 static void
50 list_cloners(void)
51 {
52 	struct if_clonereq ifcr;
53 	char *cp, *buf;
54 	int idx;
55 	int s;
56 
57 	s = socket(AF_LOCAL, SOCK_DGRAM, 0);
58 	if (s == -1)
59 		err(1, "socket(AF_LOCAL,SOCK_DGRAM)");
60 
61 	memset(&ifcr, 0, sizeof(ifcr));
62 
63 	if (ioctl(s, SIOCIFGCLONERS, &ifcr) < 0)
64 		err(1, "SIOCIFGCLONERS for count");
65 
66 	buf = malloc(ifcr.ifcr_total * IFNAMSIZ);
67 	if (buf == NULL)
68 		err(1, "unable to allocate cloner name buffer");
69 
70 	ifcr.ifcr_count = ifcr.ifcr_total;
71 	ifcr.ifcr_buffer = buf;
72 
73 	if (ioctl(s, SIOCIFGCLONERS, &ifcr) < 0)
74 		err(1, "SIOCIFGCLONERS for names");
75 
76 	/*
77 	 * In case some disappeared in the mean time, clamp it down.
78 	 */
79 	if (ifcr.ifcr_count > ifcr.ifcr_total)
80 		ifcr.ifcr_count = ifcr.ifcr_total;
81 
82 	for (cp = buf, idx = 0; idx < ifcr.ifcr_count; idx++, cp += IFNAMSIZ) {
83 		if (idx > 0)
84 			putchar(' ');
85 		printf("%s", cp);
86 	}
87 
88 	putchar('\n');
89 	free(buf);
90 }
91 
92 struct clone_defcb {
93 	char ifprefix[IFNAMSIZ];
94 	clone_callback_func *clone_cb;
95 	SLIST_ENTRY(clone_defcb) next;
96 };
97 
98 static SLIST_HEAD(, clone_defcb) clone_defcbh =
99    SLIST_HEAD_INITIALIZER(clone_defcbh);
100 
101 void
102 clone_setdefcallback(const char *ifprefix, clone_callback_func *p)
103 {
104 	struct clone_defcb *dcp;
105 
106 	dcp = malloc(sizeof(*dcp));
107 	strlcpy(dcp->ifprefix, ifprefix, IFNAMSIZ-1);
108 	dcp->clone_cb = p;
109 	SLIST_INSERT_HEAD(&clone_defcbh, dcp, next);
110 }
111 
112 /*
113  * Do the actual clone operation.  Any parameters must have been
114  * setup by now.  If a callback has been setup to do the work
115  * then defer to it; otherwise do a simple create operation with
116  * no parameters.
117  */
118 static void
119 ifclonecreate(int s, void *arg)
120 {
121 	struct ifreq ifr;
122 	struct clone_defcb *dcp;
123 	clone_callback_func *clone_cb = NULL;
124 
125 	memset(&ifr, 0, sizeof(ifr));
126 	(void) strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
127 
128 	if (clone_cb == NULL) {
129 		/* Try to find a default callback */
130 		SLIST_FOREACH(dcp, &clone_defcbh, next) {
131 			if (strncmp(dcp->ifprefix, ifr.ifr_name,
132 			    strlen(dcp->ifprefix)) == 0) {
133 				clone_cb = dcp->clone_cb;
134 				break;
135 			}
136 		}
137 	}
138 	if (clone_cb == NULL) {
139 		/* NB: no parameters */
140 		if (ioctl(s, SIOCIFCREATE2, &ifr) < 0)
141 			err(1, "SIOCIFCREATE2");
142 	} else {
143 		clone_cb(s, &ifr);
144 	}
145 
146 	/*
147 	 * If we get a different name back than we put in, print it.
148 	 */
149 	if (strncmp(name, ifr.ifr_name, sizeof(name)) != 0) {
150 		strlcpy(name, ifr.ifr_name, sizeof(name));
151 		printf("%s\n", name);
152 	}
153 }
154 
155 static
156 DECL_CMD_FUNC(clone_create, arg, d)
157 {
158 	callback_register(ifclonecreate, NULL);
159 }
160 
161 static
162 DECL_CMD_FUNC(clone_destroy, arg, d)
163 {
164 	(void) strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
165 	if (ioctl(s, SIOCIFDESTROY, &ifr) < 0)
166 		err(1, "SIOCIFDESTROY");
167 }
168 
169 static struct cmd clone_cmds[] = {
170 	DEF_CLONE_CMD("create",	0,	clone_create),
171 	DEF_CMD("destroy",	0,	clone_destroy),
172 	DEF_CLONE_CMD("plumb",	0,	clone_create),
173 	DEF_CMD("unplumb",	0,	clone_destroy),
174 };
175 
176 static void
177 clone_Copt_cb(const char *optarg __unused)
178 {
179 	list_cloners();
180 	exit(0);
181 }
182 static struct option clone_Copt = { .opt = "C", .opt_usage = "[-C]", .cb = clone_Copt_cb };
183 
184 static __constructor void
185 clone_ctor(void)
186 {
187 #define	N(a)	(sizeof(a) / sizeof(a[0]))
188 	size_t i;
189 
190 	for (i = 0; i < N(clone_cmds);  i++)
191 		cmd_register(&clone_cmds[i]);
192 	opt_register(&clone_Copt);
193 #undef N
194 }
195