xref: /freebsd/sbin/ifconfig/ifclone.c (revision eba230afba4932f02a1ca44efc797cf7499a5cb0)
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 #include <sys/param.h>
33 #include <sys/ioctl.h>
34 #include <sys/queue.h>
35 #include <sys/socket.h>
36 #include <net/if.h>
37 
38 #include <err.h>
39 #include <libifconfig.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <unistd.h>
44 
45 #include "ifconfig.h"
46 
47 typedef enum {
48 	MT_PREFIX,
49 	MT_FILTER,
50 } clone_match_type;
51 
52 static void
list_cloners(void)53 list_cloners(void)
54 {
55 	char *cloners;
56 	size_t cloners_count;
57 
58 	if (ifconfig_list_cloners(lifh, &cloners, &cloners_count) < 0)
59 		errc(1, ifconfig_err_errno(lifh), "unable to list cloners");
60 
61 	for (const char *name = cloners;
62 	    name < cloners + cloners_count * IFNAMSIZ;
63 	    name += IFNAMSIZ) {
64 		if (name > cloners)
65 			putchar(' ');
66 		printf("%s", name);
67 	}
68 	putchar('\n');
69 	free(cloners);
70 }
71 
72 struct clone_defcb {
73 	union {
74 		char ifprefix[IFNAMSIZ];
75 		clone_match_func *ifmatch;
76 	};
77 	clone_match_type clone_mt;
78 	clone_callback_func *clone_cb;
79 	SLIST_ENTRY(clone_defcb) next;
80 };
81 
82 static SLIST_HEAD(, clone_defcb) clone_defcbh =
83    SLIST_HEAD_INITIALIZER(clone_defcbh);
84 
85 void
clone_setdefcallback_prefix(const char * ifprefix,clone_callback_func * p)86 clone_setdefcallback_prefix(const char *ifprefix, clone_callback_func *p)
87 {
88 	struct clone_defcb *dcp;
89 
90 	dcp = malloc(sizeof(*dcp));
91 	strlcpy(dcp->ifprefix, ifprefix, IFNAMSIZ-1);
92 	dcp->clone_mt = MT_PREFIX;
93 	dcp->clone_cb = p;
94 	SLIST_INSERT_HEAD(&clone_defcbh, dcp, next);
95 }
96 
97 void
clone_setdefcallback_filter(clone_match_func * filter,clone_callback_func * p)98 clone_setdefcallback_filter(clone_match_func *filter, clone_callback_func *p)
99 {
100 	struct clone_defcb *dcp;
101 
102 	dcp = malloc(sizeof(*dcp));
103 	dcp->ifmatch  = filter;
104 	dcp->clone_mt = MT_FILTER;
105 	dcp->clone_cb = p;
106 	SLIST_INSERT_HEAD(&clone_defcbh, dcp, next);
107 }
108 
109 /*
110  * Do the actual clone operation.  Any parameters must have been
111  * setup by now.  If a callback has been setup to do the work
112  * then defer to it; otherwise do a simple create operation with
113  * no parameters.
114  */
115 static void
ifclonecreate(if_ctx * ctx,void * arg __unused)116 ifclonecreate(if_ctx *ctx, void *arg __unused)
117 {
118 	struct ifreq ifr = {};
119 	struct clone_defcb *dcp;
120 
121 	strlcpy(ifr.ifr_name, ctx->ifname, sizeof(ifr.ifr_name));
122 
123 	/* Try to find a default callback by filter */
124 	SLIST_FOREACH(dcp, &clone_defcbh, next) {
125 		if (dcp->clone_mt == MT_FILTER &&
126 		    dcp->ifmatch(ifr.ifr_name) != 0)
127 			break;
128 	}
129 
130 	if (dcp == NULL) {
131 		/* Try to find a default callback by prefix */
132 		SLIST_FOREACH(dcp, &clone_defcbh, next) {
133 			if (dcp->clone_mt == MT_PREFIX &&
134 			    strncmp(dcp->ifprefix, ifr.ifr_name,
135 			    strlen(dcp->ifprefix)) == 0)
136 				break;
137 		}
138 	}
139 
140 	if (dcp == NULL || dcp->clone_cb == NULL) {
141 		/* NB: no parameters */
142 		ifcreate_ioctl(ctx, &ifr);
143 	} else {
144 		dcp->clone_cb(ctx, &ifr);
145 	}
146 }
147 
148 static void
clone_create(if_ctx * ctx __unused,const char * cmd __unused,int d __unused)149 clone_create(if_ctx *ctx __unused, const char *cmd __unused, int d __unused)
150 {
151 	callback_register(ifclonecreate, NULL);
152 }
153 
154 static void
clone_destroy(if_ctx * ctx,const char * cmd __unused,int d __unused)155 clone_destroy(if_ctx *ctx, const char *cmd __unused, int d __unused)
156 {
157 	struct ifreq ifr = {};
158 
159 	if (ioctl_ctx_ifr(ctx, SIOCIFDESTROY, &ifr) < 0)
160 		err(1, "SIOCIFDESTROY");
161 }
162 
163 static struct cmd clone_cmds[] = {
164 	DEF_CLONE_CMD("create",	0,	clone_create),
165 	DEF_CMD("destroy",	0,	clone_destroy),
166 	DEF_CLONE_CMD("plumb",	0,	clone_create),
167 	DEF_CMD("unplumb",	0,	clone_destroy),
168 };
169 
170 static void
clone_Copt_cb(const char * arg __unused)171 clone_Copt_cb(const char *arg __unused)
172 {
173 	list_cloners();
174 	exit(exit_code);
175 }
176 static struct option clone_Copt = { .opt = "C", .opt_usage = "[-C]", .cb = clone_Copt_cb };
177 
178 static __constructor void
clone_ctor(void)179 clone_ctor(void)
180 {
181 	size_t i;
182 
183 	for (i = 0; i < nitems(clone_cmds);  i++)
184 		cmd_register(&clone_cmds[i]);
185 	opt_register(&clone_Copt);
186 }
187