mirror of
https://github.com/sheumann/hush.git
synced 2024-12-25 18:33:06 +00:00
6ca409e0e4
trylink: explain how to modify link and drastically decrease amount of padding (unfortunately, needs hand editing ATM). *: add ALIGN1 / ALIGN2 to global strings and arrays of bytes and shorts size saving: 0.5k
127 lines
2.4 KiB
C
127 lines
2.4 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/*
|
|
* Mini sulogin implementation for busybox
|
|
*
|
|
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
|
|
*/
|
|
|
|
#include <syslog.h>
|
|
|
|
#include "libbb.h"
|
|
|
|
static const char *const forbid[] = {
|
|
"ENV",
|
|
"BASH_ENV",
|
|
"HOME",
|
|
"IFS",
|
|
"PATH",
|
|
"SHELL",
|
|
"LD_LIBRARY_PATH",
|
|
"LD_PRELOAD",
|
|
"LD_TRACE_LOADED_OBJECTS",
|
|
"LD_BIND_NOW",
|
|
"LD_AOUT_LIBRARY_PATH",
|
|
"LD_AOUT_PRELOAD",
|
|
"LD_NOWARN",
|
|
"LD_KEEPDIR",
|
|
(char *) 0
|
|
};
|
|
|
|
|
|
static void catchalarm(int ATTRIBUTE_UNUSED junk)
|
|
{
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
|
|
int sulogin_main(int argc, char **argv);
|
|
int sulogin_main(int argc, char **argv)
|
|
{
|
|
char *cp;
|
|
int timeout = 0;
|
|
char *timeout_arg;
|
|
const char *const *p;
|
|
struct passwd *pwd;
|
|
const char *shell;
|
|
#if ENABLE_FEATURE_SHADOWPASSWDS
|
|
/* Using _r function to avoid pulling in static buffers */
|
|
char buffer[256];
|
|
struct spwd spw;
|
|
struct spwd *result;
|
|
#endif
|
|
|
|
logmode = LOGMODE_BOTH;
|
|
openlog(applet_name, 0, LOG_AUTH);
|
|
|
|
if (getopt32(argc, argv, "t:", &timeout_arg)) {
|
|
timeout = xatoi_u(timeout_arg);
|
|
}
|
|
|
|
if (argv[optind]) {
|
|
close(0);
|
|
close(1);
|
|
dup(xopen(argv[optind], O_RDWR));
|
|
close(2);
|
|
dup(0);
|
|
}
|
|
|
|
if (!isatty(0) || !isatty(1) || !isatty(2)) {
|
|
logmode = LOGMODE_SYSLOG;
|
|
bb_error_msg_and_die("not a tty");
|
|
}
|
|
|
|
/* Clear out anything dangerous from the environment */
|
|
for (p = forbid; *p; p++)
|
|
unsetenv(*p);
|
|
|
|
signal(SIGALRM, catchalarm);
|
|
|
|
pwd = getpwuid(0);
|
|
if (!pwd) {
|
|
goto auth_error;
|
|
}
|
|
|
|
#if ENABLE_FEATURE_SHADOWPASSWDS
|
|
if (getspnam_r(pwd->pw_name, &spw, buffer, sizeof(buffer), &result)) {
|
|
goto auth_error;
|
|
}
|
|
pwd->pw_passwd = spw.sp_pwdp;
|
|
#endif
|
|
|
|
while (1) {
|
|
/* cp points to a static buffer that is zeroed every time */
|
|
cp = bb_askpass(timeout,
|
|
"Give root password for system maintenance\n"
|
|
"(or type Control-D for normal startup):");
|
|
|
|
if (!cp || !*cp) {
|
|
bb_info_msg("Normal startup");
|
|
return 0;
|
|
}
|
|
if (strcmp(pw_encrypt(cp, pwd->pw_passwd), pwd->pw_passwd) == 0) {
|
|
break;
|
|
}
|
|
bb_do_delay(FAIL_DELAY);
|
|
bb_error_msg("login incorrect");
|
|
}
|
|
memset(cp, 0, strlen(cp));
|
|
signal(SIGALRM, SIG_DFL);
|
|
|
|
bb_info_msg("System Maintenance Mode");
|
|
|
|
USE_SELINUX(renew_current_security_context());
|
|
|
|
shell = getenv("SUSHELL");
|
|
if (!shell) shell = getenv("sushell");
|
|
if (!shell) {
|
|
shell = "/bin/sh";
|
|
if (pwd->pw_shell[0])
|
|
shell = pwd->pw_shell;
|
|
}
|
|
run_shell(shell, 1, 0, 0);
|
|
/* never returns */
|
|
|
|
auth_error:
|
|
bb_error_msg_and_die("no password entry for 'root'");
|
|
}
|