xref: /illumos-gate/usr/src/cmd/modload/modunload.c (revision abdf5d9abf528d6c318fd8533e09bc3cac1f228b)
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 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/types.h>
27 #include <sys/mman.h>
28 #include <sys/stat.h>
29 #include <sys/wait.h>
30 #include <strings.h>
31 #include <unistd.h>
32 #include <errno.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <sys/modctl.h>
36 #include <zone.h>
37 
38 void	usage();
39 void	exec_userfile(char *execfile, int id, char **envp);
40 
41 extern void fatal(char *fmt, ...);
42 extern void error(char *fmt, ...);
43 
44 /*
45  * Unload a loaded module.
46  */
47 int
48 main(int argc, char *argv[], char *envp[])
49 {
50 	int child;
51 	int status;
52 	int id;
53 	char *execfile = NULL;
54 	int opt;
55 	extern char *optarg;
56 
57 	if (argc < 3)
58 		usage();
59 
60 	while ((opt = getopt(argc, argv, "i:e:")) != -1) {
61 		switch (opt) {
62 		case 'i':
63 			if (sscanf(optarg, "%d", &id) != 1)
64 				fatal("Invalid id %s\n", optarg);
65 			break;
66 		case 'e':
67 			execfile = optarg;
68 		}
69 	}
70 
71 	if (getzoneid() != GLOBAL_ZONEID) {
72 		fatal("modunload can only be run from the global zone\n");
73 	}
74 
75 	if (execfile) {
76 		child = fork();
77 		if (child == -1)
78 			error("can't fork %s", execfile);
79 		else if (child == 0)
80 			exec_userfile(execfile, id, envp);
81 		else {
82 			(void) wait(&status);
83 			if (status != 0) {
84 				(void) printf("%s returned error %d.\n",
85 				    execfile, status);
86 				(void) exit(status >> 8);
87 			}
88 		}
89 	}
90 
91 	/*
92 	 * Unload the module.
93 	 */
94 	if (modctl(MODUNLOAD, id) < 0) {
95 		if (errno == EPERM)
96 			fatal("Insufficient privileges to unload a module\n");
97 		else if (id != 0)
98 			error("can't unload the module");
99 	}
100 
101 	return (0);			/* success */
102 }
103 
104 /*
105  * exec the user file.
106  */
107 void
108 exec_userfile(char *execfile, int id, char **envp)
109 {
110 	struct modinfo modinfo;
111 
112 	char modid[8];
113 	char mod0[8];
114 
115 	modinfo.mi_id = modinfo.mi_nextid = id;
116 	modinfo.mi_info = MI_INFO_ONE;
117 	if (modctl(MODINFO, id, &modinfo) < 0)
118 		error("can't get module information");
119 
120 	(void) sprintf(modid, "%d", id);
121 	(void) sprintf(mod0, "%d", modinfo.mi_msinfo[0].msi_p0);
122 
123 	(void) execle(execfile, execfile, modid, mod0, NULL, envp);
124 
125 	error("couldn't exec %s\n", execfile);
126 }
127 
128 
129 void
130 usage()
131 {
132 	fatal("usage:  modunload -i <module_id> [-e <exec_file>]\n");
133 }
134