source: MondoRescue/branches/3.3/mindi-busybox/loginutils/chpasswd.c@ 3621

/* vi: set sw=4 ts=4: */
/*
 * chpasswd.c
 *
 * Written for SLIND (from passwd.c) by Alexander Shishkin <virtuoso@slind.org>
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
//config:config CHPASSWD
//config:   bool "chpasswd"
//config:   default y
//config:   help
//config:     Reads a file of user name and password pairs from standard input
//config:     and uses this information to update a group of existing users.
//config:
//config:config FEATURE_DEFAULT_PASSWD_ALGO
//config:   string "Default password encryption method (passwd -a, cryptpw -m parameter)"
//config:   default "des"
//config:   depends on PASSWD || CRYPTPW
//config:   help
//config:     Possible choices are "d[es]", "m[d5]", "s[ha256]" or "sha512".

//applet:IF_CHPASSWD(APPLET(chpasswd, BB_DIR_USR_SBIN, BB_SUID_DROP))

//kbuild:lib-$(CONFIG_CHPASSWD) += chpasswd.o

//usage:#define chpasswd_trivial_usage
//usage:    IF_LONG_OPTS("[--md5|--encrypted|--crypt-method]") IF_NOT_LONG_OPTS("[-m|-e|-c]")
//usage:#define chpasswd_full_usage "\n\n"
//usage:       "Read user:password from stdin and update /etc/passwd\n"
//usage:    IF_LONG_OPTS(
//usage:     "\n    -e,--encrypted      Supplied passwords are in encrypted form"
//usage:     "\n    -m,--md5        Use MD5 encryption instead of DES"
//usage:     "\n    -c,--crypt-method   Use the specified method to encrypt the passwords"
//usage:    )
//usage:    IF_NOT_LONG_OPTS(
//usage:     "\n    -e  Supplied passwords are in encrypted form"
//usage:     "\n    -m  Use MD5 encryption instead of DES"
//usage:     "\n    -c  Use the specified method to encrypt the passwords"
//usage:    )

#include "libbb.h"

#if ENABLE_LONG_OPTS
static const char chpasswd_longopts[] ALIGN1 =
    "encrypted\0"    No_argument       "e"
    "md5\0"          No_argument       "m"
    "crypt-method\0" Required_argument "c"
    ;
#endif

#define OPT_ENC  1
#define OPT_MD5  2

int chpasswd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int chpasswd_main(int argc UNUSED_PARAM, char **argv)
{
    char *name;
    const char *algo = CONFIG_FEATURE_DEFAULT_PASSWD_ALGO;
    int opt;

    if (getuid() != 0)
        bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);

    opt_complementary = "m--ec:e--mc:c--em";
    IF_LONG_OPTS(applet_long_options = chpasswd_longopts;)
    opt = getopt32(argv, "emc:", &algo);

    while ((name = xmalloc_fgetline(stdin)) != NULL) {
        char *free_me;
        char *pass;
        int rc;

        pass = strchr(name, ':');
        if (!pass)
            bb_error_msg_and_die("missing new password");
        *pass++ = '\0';

        xuname2uid(name); /* dies if there is no such user */

        free_me = NULL;
        if (!(opt & OPT_ENC)) {
            char salt[MAX_PW_SALT_LEN];

            if (opt & OPT_MD5) {
                /* Force MD5 if the -m flag is set */
                algo = "md5";
            }

            crypt_make_pw_salt(salt, algo);
            free_me = pass = pw_encrypt(pass, salt, 0);
        }

        /* This is rather complex: if user is not found in /etc/shadow,
         * we try to find & change his passwd in /etc/passwd */
#if ENABLE_FEATURE_SHADOWPASSWDS
        rc = update_passwd(bb_path_shadow_file, name, pass, NULL);
        if (rc > 0) /* password in /etc/shadow was updated */
            pass = (char*)"x";
        if (rc >= 0)
            /* 0 = /etc/shadow missing (not an error), >0 = passwd changed in /etc/shadow */
#endif
            rc = update_passwd(bb_path_passwd_file, name, pass, NULL);
        /* LOGMODE_BOTH logs to syslog also */
        logmode = LOGMODE_BOTH;
        if (rc < 0)
            bb_error_msg_and_die("an error occurred updating password for %s", name);
        if (rc)
            bb_error_msg("password for '%s' changed", name);
        logmode = LOGMODE_STDIO;
        free(name);
        free(free_me);
    }
    return EXIT_SUCCESS;
}