Contents of /tags/mkinitrd-6_1_6/busybox/loginutils/sulogin.c
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Wed Aug 5 19:21:45 2009 UTC (15 years, 1 month ago) by niro
File MIME type: text/plain
File size: 2546 byte(s)
Wed Aug 5 19:21:45 2009 UTC (15 years, 1 month ago) by niro
File MIME type: text/plain
File size: 2546 byte(s)
tagged 'mkinitrd-6_1_6'
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * Mini sulogin implementation for busybox |
4 | * |
5 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
6 | */ |
7 | |
8 | #include "libbb.h" |
9 | #include <syslog.h> |
10 | |
11 | //static void catchalarm(int UNUSED_PARAM junk) |
12 | //{ |
13 | // exit(EXIT_FAILURE); |
14 | //} |
15 | |
16 | |
17 | int sulogin_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
18 | int sulogin_main(int argc UNUSED_PARAM, char **argv) |
19 | { |
20 | char *cp; |
21 | int timeout = 0; |
22 | struct passwd *pwd; |
23 | const char *shell; |
24 | #if ENABLE_FEATURE_SHADOWPASSWDS |
25 | /* Using _r function to avoid pulling in static buffers */ |
26 | char buffer[256]; |
27 | struct spwd spw; |
28 | #endif |
29 | |
30 | logmode = LOGMODE_BOTH; |
31 | openlog(applet_name, 0, LOG_AUTH); |
32 | |
33 | opt_complementary = "t+"; /* -t N */ |
34 | getopt32(argv, "t:", &timeout); |
35 | argv += optind; |
36 | |
37 | if (argv[0]) { |
38 | close(0); |
39 | close(1); |
40 | dup(xopen(argv[0], O_RDWR)); |
41 | close(2); |
42 | dup(0); |
43 | } |
44 | |
45 | /* Malicious use like "sulogin /dev/sda"? */ |
46 | if (!isatty(0) || !isatty(1) || !isatty(2)) { |
47 | logmode = LOGMODE_SYSLOG; |
48 | bb_error_msg_and_die("not a tty"); |
49 | } |
50 | |
51 | /* Clear dangerous stuff, set PATH */ |
52 | sanitize_env_if_suid(); |
53 | |
54 | // bb_askpass() already handles this |
55 | // signal(SIGALRM, catchalarm); |
56 | |
57 | pwd = getpwuid(0); |
58 | if (!pwd) { |
59 | goto auth_error; |
60 | } |
61 | |
62 | #if ENABLE_FEATURE_SHADOWPASSWDS |
63 | { |
64 | /* getspnam_r may return 0 yet set result to NULL. |
65 | * At least glibc 2.4 does this. Be extra paranoid here. */ |
66 | struct spwd *result = NULL; |
67 | int r = getspnam_r(pwd->pw_name, &spw, buffer, sizeof(buffer), &result); |
68 | if (r || !result) { |
69 | goto auth_error; |
70 | } |
71 | pwd->pw_passwd = result->sp_pwdp; |
72 | } |
73 | #endif |
74 | |
75 | while (1) { |
76 | char *encrypted; |
77 | int r; |
78 | |
79 | /* cp points to a static buffer that is zeroed every time */ |
80 | cp = bb_askpass(timeout, |
81 | "Give root password for system maintenance\n" |
82 | "(or type Control-D for normal startup):"); |
83 | |
84 | if (!cp || !*cp) { |
85 | bb_info_msg("Normal startup"); |
86 | return 0; |
87 | } |
88 | encrypted = pw_encrypt(cp, pwd->pw_passwd, 1); |
89 | r = strcmp(encrypted, pwd->pw_passwd); |
90 | free(encrypted); |
91 | if (r == 0) { |
92 | break; |
93 | } |
94 | bb_do_delay(FAIL_DELAY); |
95 | bb_error_msg("login incorrect"); |
96 | } |
97 | memset(cp, 0, strlen(cp)); |
98 | // signal(SIGALRM, SIG_DFL); |
99 | |
100 | bb_info_msg("System Maintenance Mode"); |
101 | |
102 | USE_SELINUX(renew_current_security_context()); |
103 | |
104 | shell = getenv("SUSHELL"); |
105 | if (!shell) |
106 | shell = getenv("sushell"); |
107 | if (!shell) { |
108 | shell = "/bin/sh"; |
109 | if (pwd->pw_shell[0]) |
110 | shell = pwd->pw_shell; |
111 | } |
112 | /* Exec login shell with no additional parameters. Never returns. */ |
113 | run_shell(shell, 1, NULL, NULL); |
114 | |
115 | auth_error: |
116 | bb_error_msg_and_die("no password entry for root"); |
117 | } |