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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
/* vi: set sw=4 ts=4: */
/*
* vlock implementation for busybox
*
* Copyright (C) 2000 by spoon <spoon@ix.netcom.com>
* Written by spoon <spon@ix.netcom.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
/* Shoutz to Michael K. Johnson <johnsonm@redhat.com>, author of the
* original vlock. I snagged a bunch of his code to write this
* minimalistic vlock.
*/
/* Fixed by Erik Andersen to do passwords the tinylogin way...
* It now works with md5, sha1, etc passwords. */
#include <stdio.h>
#include <stdlib.h>
#include <sys/vt.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <termios.h>
#include "busybox.h"
static struct passwd *pw;
static struct vt_mode ovtm;
static struct termios oterm;
static int vfd;
static int o_lock_all = 0;
#ifdef CONFIG_FEATURE_SHADOWPASSWDS
static struct spwd *spw;
/* getspuid - get a shadow entry by uid */
struct spwd *getspuid(uid_t uid)
{
struct spwd *sp;
struct passwd *mypw;
if ((mypw = getpwuid(getuid())) == NULL) {
return (NULL);
}
setspent();
while ((sp = getspent()) != NULL) {
if (strcmp(mypw->pw_name, sp->sp_namp) == 0)
break;
}
endspent();
return (sp);
}
#endif
static void release_vt(int signo)
{
if (!o_lock_all)
ioctl(vfd, VT_RELDISP, 1);
else
ioctl(vfd, VT_RELDISP, 0);
}
static void acquire_vt(int signo)
{
ioctl(vfd, VT_RELDISP, VT_ACKACQ);
}
static void restore_terminal(void)
{
ioctl(vfd, VT_SETMODE, &ovtm);
tcsetattr(STDIN_FILENO, TCSANOW, &oterm);
}
extern int vlock_main(int argc, char **argv)
{
sigset_t sig;
struct sigaction sa;
struct vt_mode vtm;
int times = 0;
struct termios term;
if (argc > 2) {
bb_show_usage();
}
if (argc == 2) {
if (strncmp(argv[1], "-a", 2)) {
bb_show_usage();
} else {
o_lock_all = 1;
}
}
if ((pw = getpwuid(getuid())) == NULL) {
bb_error_msg_and_die("no password for uid %d\n", getuid());
}
#ifdef CONFIG_FEATURE_SHADOWPASSWDS
if ((strcmp(pw->pw_passwd, "x") == 0)
|| (strcmp(pw->pw_passwd, "*") == 0)) {
if ((spw = getspuid(getuid())) == NULL) {
bb_error_msg_and_die("could not read shadow password for uid %d: %s\n",
getuid(), strerror(errno));
}
if (spw->sp_pwdp) {
pw->pw_passwd = spw->sp_pwdp;
}
}
#endif /* CONFIG_FEATURE_SHADOWPASSWDS */
if (pw->pw_passwd[0] == '!' || pw->pw_passwd[0] == '*') {
bb_error_msg_and_die("Account disabled for uid %d\n", getuid());
}
/* we no longer need root privs */
setuid(getuid());
setgid(getgid());
if ((vfd = open("/dev/tty", O_RDWR)) < 0) {
bb_error_msg_and_die("/dev/tty");
};
if (ioctl(vfd, VT_GETMODE, &vtm) < 0) {
bb_error_msg_and_die("/dev/tty");
};
/* mask a bunch of signals */
sigprocmask(SIG_SETMASK, NULL, &sig);
sigdelset(&sig, SIGUSR1);
sigdelset(&sig, SIGUSR2);
sigaddset(&sig, SIGTSTP);
sigaddset(&sig, SIGTTIN);
sigaddset(&sig, SIGTTOU);
sigaddset(&sig, SIGHUP);
sigaddset(&sig, SIGCHLD);
sigaddset(&sig, SIGQUIT);
sigaddset(&sig, SIGINT);
sigemptyset(&(sa.sa_mask));
sa.sa_flags = SA_RESTART;
sa.sa_handler = release_vt;
sigaction(SIGUSR1, &sa, NULL);
sa.sa_handler = acquire_vt;
sigaction(SIGUSR2, &sa, NULL);
/* need to handle some signals so that we don't get killed by them */
sa.sa_handler = SIG_IGN;
sigaction(SIGHUP, &sa, NULL);
sigaction(SIGQUIT, &sa, NULL);
sigaction(SIGINT, &sa, NULL);
sigaction(SIGTSTP, &sa, NULL);
ovtm = vtm;
vtm.mode = VT_PROCESS;
vtm.relsig = SIGUSR1;
vtm.acqsig = SIGUSR2;
ioctl(vfd, VT_SETMODE, &vtm);
tcgetattr(STDIN_FILENO, &oterm);
term = oterm;
term.c_iflag &= ~BRKINT;
term.c_iflag |= IGNBRK;
term.c_lflag &= ~ISIG;
term.c_lflag &= ~(ECHO | ECHOCTL);
tcsetattr(STDIN_FILENO, TCSANOW, &term);
do {
char *pass, *crypt_pass;
char prompt[100];
if (o_lock_all) {
printf("All Virtual Consoles locked.\n");
} else {
printf("This Virtual Console locked.\n");
}
fflush(stdout);
snprintf(prompt, 100, "%s's password: ", pw->pw_name);
if ((pass = getpass(prompt)) == NULL) {
perror("getpass");
restore_terminal();
exit(1);
}
crypt_pass = pw_encrypt(pass, pw->pw_passwd);
if (strncmp(crypt_pass, pw->pw_passwd, sizeof(crypt_pass)) == 0) {
memset(pass, 0, strlen(pass));
memset(crypt_pass, 0, strlen(crypt_pass));
restore_terminal();
return 0;
}
memset(pass, 0, strlen(pass));
memset(crypt_pass, 0, strlen(crypt_pass));
if (isatty(STDIN_FILENO) == 0) {
perror("isatty");
restore_terminal();
exit(1);
}
sleep(++times);
printf("Password incorrect.\n");
if (times >= 3) {
sleep(15);
times = 2;
}
} while (1);
}
/*
Local Variables:
c-file-style: "linux"
c-basic-offset: 4
tab-width: 4
End:
*/
|
