ndk-busybox/libbb/run_shell.c
Denys Vlasenko f4f6e5144b libbb: exec_login_shell() - new function
function                                             old     new   delta
exec_login_shell                                       -      12     +12
sulogin_main                                         247     240      -7
login_main                                           960     953      -7
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/2 up/down: 12/-14)             Total: -2 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-12-02 21:51:08 +01:00

103 lines
3.3 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Copyright 1989 - 1991, Julianne Frances Haugh <jockgrrl@austin.rr.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Julianne F. Haugh nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ''AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "libbb.h"
#if ENABLE_SELINUX
#include <selinux/selinux.h> /* for setexeccon */
#endif
#if ENABLE_SELINUX
static security_context_t current_sid;
void FAST_FUNC renew_current_security_context(void)
{
freecon(current_sid); /* Release old context */
getcon(&current_sid); /* update */
}
void FAST_FUNC set_current_security_context(security_context_t sid)
{
freecon(current_sid); /* Release old context */
current_sid = sid;
}
#endif
/* Exec SHELL, or DEFAULT_SHELL if SHELL is "" or NULL.
* If ADDITIONAL_ARGS is not NULL, pass them to the shell.
*/
void FAST_FUNC exec_shell(const char *shell, int loginshell, const char **additional_args)
{
const char **args;
args = additional_args;
while (args && *args)
args++;
args = xzalloc(sizeof(args[0]) * (2 + (args - additional_args)));
if (!shell || !shell[0])
shell = DEFAULT_SHELL;
args[0] = bb_get_last_path_component_nostrip(shell);
if (loginshell)
args[0] = xasprintf("-%s", args[0]);
/*args[1] = NULL; - already is */
if (additional_args) {
int cnt = 0;
while (*additional_args)
args[++cnt] = *additional_args++;
}
#if ENABLE_SELINUX
if (current_sid)
setexeccon(current_sid);
if (ENABLE_FEATURE_CLEAN_UP)
freecon(current_sid);
#endif
execv(shell, (char **) args);
bb_perror_msg_and_die("can't execute '%s'", shell);
}
void FAST_FUNC exec_login_shell(const char *shell)
{
exec_shell(shell, 1, NULL);
}
/* Typical idiom for applets which exec *optional* PROG [ARGS] */
void FAST_FUNC exec_prog_or_SHELL(char **argv)
{
if (argv[0]) {
BB_EXECVP_or_die(argv);
}
/* Both users (nsenter and unshare) do indeed exec
* a _login_ shell (with dash in argv[0])!
*/
exec_login_shell(getenv("SHELL"));
}