LXR busybox/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:        "[-me] [-c ALG] [-R DIR]"
  28//usage:#define chpasswd_full_usage "\n\n"
  29//usage:       "Read user:password from stdin and update /etc/passwd\n"
  30//usage:     "\n        -e      Supplied passwords are in encrypted form"
  31//usage:     "\n        -m      Encrypt using md5, not des"
  32//usage:     "\n        -c ALG  "CRYPT_METHODS_HELP_STR
  33//usage:     "\n        -R DIR  Directory to chroot into"
  34
  35#include "libbb.h"
  36
  37#if ENABLE_LONG_OPTS
  38static const char chpasswd_longopts[] ALIGN1 =
  39        "encrypted\0"    No_argument       "e"
  40        "md5\0"          No_argument       "m"
  41        "crypt-method\0" Required_argument "c"
  42        "root\0"         Required_argument "R"
  43        ;
  44#endif
  45
  46#define OPT_ENC  1
  47#define OPT_MD5  2
  48
  49int chpasswd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  50int chpasswd_main(int argc UNUSED_PARAM, char **argv)
  51{
  52        char *name;
  53        const char *algo = CONFIG_FEATURE_DEFAULT_PASSWD_ALGO;
  54        const char *root = NULL;
  55        int opt;
  56
  57        if (getuid() != 0)
  58                bb_simple_error_msg_and_die(bb_msg_perm_denied_are_you_root);
  59
  60        opt = getopt32long(argv, "^" "emc:R:" "\0" "m--ec:e--mc:c--em",
  61                        chpasswd_longopts,
  62                        &algo, &root
  63        );
  64
  65        if (root) {
  66                xchroot(root);
  67        }
  68
  69        while ((name = xmalloc_fgetline(stdin)) != NULL) {
  70                char *free_me;
  71                char *pass;
  72                int rc;
  73
  74                pass = strchr(name, ':');
  75                if (!pass)
  76                        bb_simple_error_msg_and_die("missing new password");
  77                *pass++ = '\0';
  78
  79                xuname2uid(name); /* dies if there is no such user */
  80
  81                free_me = NULL;
  82                if (!(opt & OPT_ENC)) {
  83                        char salt[MAX_PW_SALT_LEN];
  84
  85                        if (opt & OPT_MD5) {
  86                                /* Force MD5 if the -m flag is set */
  87                                algo = "md5";
  88                        }
  89
  90                        crypt_make_pw_salt(salt, algo);
  91                        free_me = pass = pw_encrypt(pass, salt, 0);
  92                }
  93
  94                /* This is rather complex: if user is not found in /etc/shadow,
  95                 * we try to find & change his passwd in /etc/passwd */
  96#if ENABLE_FEATURE_SHADOWPASSWDS
  97                rc = update_passwd(bb_path_shadow_file, name, pass, NULL);
  98                if (rc > 0) /* password in /etc/shadow was updated */
  99                        pass = (char*)"x";
 100                if (rc >= 0)
 101                        /* 0 = /etc/shadow missing (not an error), >0 = passwd changed in /etc/shadow */
 102#endif
 103                        rc = update_passwd(bb_path_passwd_file, name, pass, NULL);
 104                /* LOGMODE_BOTH logs to syslog also */
 105                logmode = LOGMODE_BOTH;
 106                if (rc < 0)
 107                        bb_error_msg_and_die("an error occurred updating password for %s", name);
 108                if (rc)
 109                        bb_info_msg("password for '%s' changed", name);
 110                logmode = LOGMODE_STDIO;
 111                free(name);
 112                free(free_me);
 113        }
 114        return EXIT_SUCCESS;
 115}
 116