1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
/* 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 forbid[] ALIGN1 =
"ENV" "\0"
"BASH_ENV" "\0"
"HOME" "\0"
"IFS" "\0"
"PATH" "\0"
"SHELL" "\0"
"LD_LIBRARY_PATH" "\0"
"LD_PRELOAD" "\0"
"LD_TRACE_LOADED_OBJECTS" "\0"
"LD_BIND_NOW" "\0"
"LD_AOUT_LIBRARY_PATH" "\0"
"LD_AOUT_PRELOAD" "\0"
"LD_NOWARN" "\0"
"LD_KEEPDIR" "\0";
//static void catchalarm(int ATTRIBUTE_UNUSED junk)
//{
// exit(EXIT_FAILURE);
//}
int sulogin_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int sulogin_main(int argc, char **argv)
{
char *cp;
int timeout = 0;
char *timeout_arg;
const char *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;
#endif
logmode = LOGMODE_BOTH;
openlog(applet_name, 0, LOG_AUTH);
if (getopt32(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 */
p = forbid;
do {
unsetenv(p);
p += strlen(p) + 1;
} while (*p);
// bb_askpass() already handles this
// signal(SIGALRM, catchalarm);
pwd = getpwuid(0);
if (!pwd) {
goto auth_error;
}
#if ENABLE_FEATURE_SHADOWPASSWDS
{
/* getspnam_r may return 0 yet set result to NULL.
* At least glibc 2.4 does this. Be extra paranoid here. */
struct spwd *result = NULL;
int r = getspnam_r(pwd->pw_name, &spw, buffer, sizeof(buffer), &result);
if (r || !result) {
goto auth_error;
}
pwd->pw_passwd = result->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;
}
/* Exec login shell with no additional parameters. Never returns. */
run_shell(shell, 1, NULL, NULL);
auth_error:
bb_error_msg_and_die("no password entry for root");
}
|
