1/* vi: set sw=4 ts=4: */
2/*
3 * Copyright 1989 - 1991, Julianne Frances Haugh <jockgrrl@austin.rr.com>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of Julianne F. Haugh nor the names of its contributors
15 *    may be used to endorse or promote products derived from this software
16 *    without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31#include "libbb.h"
32#if ENABLE_SELINUX
33#include <selinux/selinux.h>  /* for setexeccon  */
34#endif
35
36#if ENABLE_SELINUX
37static security_context_t current_sid;
38
39void
40renew_current_security_context(void)
41{
42	if (current_sid)
43		freecon(current_sid);  /* Release old context  */
44	getcon(&current_sid);  /* update */
45}
46void
47set_current_security_context(security_context_t sid)
48{
49	if (current_sid)
50		freecon(current_sid);  /* Release old context  */
51	current_sid = sid;
52}
53
54#endif
55
56/* Run SHELL, or DEFAULT_SHELL if SHELL is empty.
57   If COMMAND is nonzero, pass it to the shell with the -c option.
58   If ADDITIONAL_ARGS is nonzero, pass it to the shell as more
59   arguments.  */
60
61void run_shell(const char *shell, int loginshell, const char *command, const char **additional_args)
62{
63	const char **args;
64	int argno = 1;
65	int additional_args_cnt = 0;
66
67	for (args = additional_args; args && *args; args++)
68		additional_args_cnt++;
69
70	args = xmalloc(sizeof(char*) * (4 + additional_args_cnt));
71
72	args[0] = bb_get_last_path_component(xstrdup(shell));
73
74	if (loginshell)
75		args[0] = xasprintf("-%s", args[0]);
76
77	if (command) {
78		args[argno++] = "-c";
79		args[argno++] = command;
80	}
81	if (additional_args) {
82		for (; *additional_args; ++additional_args)
83			args[argno++] = *additional_args;
84	}
85	args[argno] = NULL;
86#if ENABLE_SELINUX
87	if (current_sid && !setexeccon(current_sid)) {
88		freecon(current_sid);
89		execve(shell, (char **) args, environ);
90	} else
91#endif
92	execv(shell, (char **) args);
93	bb_perror_msg_and_die("cannot run %s", shell);
94}
95