tls: prepare for ECDH_anon ciphers
[oweals/busybox.git] / loginutils / chpasswd.c
1 /* vi: set sw=4 ts=4: */
2 /*
3  * chpasswd.c
4  *
5  * Written for SLIND (from passwd.c) by Alexander Shishkin <virtuoso@slind.org>
6  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
7  */
8 //config:config CHPASSWD
9 //config:       bool "chpasswd (18 kb)"
10 //config:       default y
11 //config:       help
12 //config:       Reads a file of user name and password pairs from standard input
13 //config:       and uses this information to update a group of existing users.
14 //config:
15 //config:config FEATURE_DEFAULT_PASSWD_ALGO
16 //config:       string "Default encryption method (passwd -a, cryptpw -m, chpasswd -c ALG)"
17 //config:       default "des"
18 //config:       depends on PASSWD || CRYPTPW || CHPASSWD
19 //config:       help
20 //config:       Possible choices are "d[es]", "m[d5]", "s[ha256]" or "sha512".
21
22 //applet:IF_CHPASSWD(APPLET(chpasswd, BB_DIR_USR_SBIN, BB_SUID_DROP))
23
24 //kbuild:lib-$(CONFIG_CHPASSWD) += chpasswd.o
25
26 //usage:#define chpasswd_trivial_usage
27 //usage:        IF_LONG_OPTS("[--md5|--encrypted|--crypt-method|--root]") IF_NOT_LONG_OPTS("[-m|-e|-c|-R]")
28 //usage:#define chpasswd_full_usage "\n\n"
29 //usage:       "Read user:password from stdin and update /etc/passwd\n"
30 //usage:        IF_LONG_OPTS(
31 //usage:     "\n        -e,--encrypted          Supplied passwords are in encrypted form"
32 //usage:     "\n        -m,--md5                Encrypt using md5, not des"
33 //usage:     "\n        -c,--crypt-method ALG   "CRYPT_METHODS_HELP_STR
34 //usage:     "\n        -R,--root DIR           Directory to chroot into"
35 //usage:        )
36 //usage:        IF_NOT_LONG_OPTS(
37 //usage:     "\n        -e      Supplied passwords are in encrypted form"
38 //usage:     "\n        -m      Encrypt using md5, not des"
39 //usage:     "\n        -c ALG  "CRYPT_METHODS_HELP_STR
40 //usage:     "\n        -R DIR  Directory to chroot into"
41 //usage:        )
42
43 #include "libbb.h"
44
45 #if ENABLE_LONG_OPTS
46 static const char chpasswd_longopts[] ALIGN1 =
47         "encrypted\0"    No_argument       "e"
48         "md5\0"          No_argument       "m"
49         "crypt-method\0" Required_argument "c"
50         "root\0"         Required_argument "R"
51         ;
52 #endif
53
54 #define OPT_ENC  1
55 #define OPT_MD5  2
56
57 int chpasswd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
58 int chpasswd_main(int argc UNUSED_PARAM, char **argv)
59 {
60         char *name;
61         const char *algo = CONFIG_FEATURE_DEFAULT_PASSWD_ALGO;
62         const char *root = NULL;
63         int opt;
64
65         if (getuid() != 0)
66                 bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
67
68         opt = getopt32long(argv, "^" "emc:R:" "\0" "m--ec:e--mc:c--em",
69                         chpasswd_longopts,
70                         &algo, &root
71         );
72
73         if (root) {
74                 xchroot(root);
75         }
76
77         while ((name = xmalloc_fgetline(stdin)) != NULL) {
78                 char *free_me;
79                 char *pass;
80                 int rc;
81
82                 pass = strchr(name, ':');
83                 if (!pass)
84                         bb_error_msg_and_die("missing new password");
85                 *pass++ = '\0';
86
87                 xuname2uid(name); /* dies if there is no such user */
88
89                 free_me = NULL;
90                 if (!(opt & OPT_ENC)) {
91                         char salt[MAX_PW_SALT_LEN];
92
93                         if (opt & OPT_MD5) {
94                                 /* Force MD5 if the -m flag is set */
95                                 algo = "md5";
96                         }
97
98                         crypt_make_pw_salt(salt, algo);
99                         free_me = pass = pw_encrypt(pass, salt, 0);
100                 }
101
102                 /* This is rather complex: if user is not found in /etc/shadow,
103                  * we try to find & change his passwd in /etc/passwd */
104 #if ENABLE_FEATURE_SHADOWPASSWDS
105                 rc = update_passwd(bb_path_shadow_file, name, pass, NULL);
106                 if (rc > 0) /* password in /etc/shadow was updated */
107                         pass = (char*)"x";
108                 if (rc >= 0)
109                         /* 0 = /etc/shadow missing (not an error), >0 = passwd changed in /etc/shadow */
110 #endif
111                         rc = update_passwd(bb_path_passwd_file, name, pass, NULL);
112                 /* LOGMODE_BOTH logs to syslog also */
113                 logmode = LOGMODE_BOTH;
114                 if (rc < 0)
115                         bb_error_msg_and_die("an error occurred updating password for %s", name);
116                 if (rc)
117                         bb_error_msg("password for '%s' changed", name);
118                 logmode = LOGMODE_STDIO;
119                 free(name);
120                 free(free_me);
121         }
122         return EXIT_SUCCESS;
123 }