LXR busybox/loginutils/cryptpw.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * cryptpw.c - output a crypt(3)ed password to stdout.
   4 *
   5 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   6 *
   7 * Cooked from passwd.c by Thomas Lundquist <thomasez@zelow.no>
   8 * mkpasswd compatible options added by Bernhard Reutner-Fischer
   9 *
  10 * Licensed under GPLv2, see file LICENSE in this source tree.
  11 */
  12//config:config CRYPTPW
  13//config:       bool "cryptpw (14 kb)"
  14//config:       default y
  15//config:       help
  16//config:       Encrypts the given password with the crypt(3) libc function
  17//config:       using the given salt.
  18//config:
  19//config:config MKPASSWD
  20//config:       bool "mkpasswd (15 kb)"
  21//config:       default y
  22//config:       help
  23//config:       Encrypts the given password with the crypt(3) libc function
  24//config:       using the given salt. Debian has this utility under mkpasswd
  25//config:       name. Busybox provides mkpasswd as an alias for cryptpw.
  26
  27//applet:IF_CRYPTPW( APPLET_NOEXEC(cryptpw,  cryptpw, BB_DIR_USR_BIN, BB_SUID_DROP, cryptpw))
  28//                   APPLET_NOEXEC:name      main     location        suid_type     help
  29//applet:IF_MKPASSWD(APPLET_NOEXEC(mkpasswd, cryptpw, BB_DIR_USR_BIN, BB_SUID_DROP, cryptpw))
  30
  31//kbuild:lib-$(CONFIG_CRYPTPW) += cryptpw.o
  32//kbuild:lib-$(CONFIG_MKPASSWD) += cryptpw.o
  33
  34//usage:#define cryptpw_trivial_usage
  35//usage:       "[-P FD] [-m TYPE] [-S SALT] [PASSWORD] [SALT]"
  36/* We do support -s, we just don't mention it */
  37//usage:#define cryptpw_full_usage "\n\n"
  38//usage:       "Print crypt(3) hashed PASSWORD\n"
  39//usage:     "\n        -P N    Read password from fd N"
  40/* //usage:  "\n        -s      Use stdin; like -P0" */
  41//usage:     "\n        -m TYPE "CRYPT_METHODS_HELP_STR
  42//usage:     "\n        -S SALT"
  43
  44#include "libbb.h"
  45
  46/* Debian has 'mkpasswd' utility, manpage says:
  47
  48NAME
  49    mkpasswd - Overfeatured front end to crypt(3)
  50SYNOPSIS
  51    mkpasswd PASSWORD SALT
  52...
  53OPTIONS
  54-S, --salt=STRING
  55    Use the STRING as salt. It must not  contain  prefixes  such  as
  56    $1$.
  57-R, --rounds=NUMBER
  58    Use NUMBER rounds. This argument is ignored if the method
  59    chosen does not support variable rounds. For the OpenBSD Blowfish
  60    method this is the logarithm of the number of rounds.
  61-m, --method=TYPE
  62    Compute the password using the TYPE method. If TYPE is 'help'
  63    then the available methods are printed.
  64-P, --password-fd=NUM
  65    Read the password from file descriptor NUM instead of using getpass(3).
  66    If the file descriptor is not connected to a tty then
  67    no other message than the hashed password is printed on stdout.
  68-s, --stdin
  69    Like --password-fd=0.
  70ENVIRONMENT
  71    $MKPASSWD_OPTIONS
  72    A list of options which will be evaluated before the ones
  73    specified on the command line.
  74BUGS
  75    This program suffers of a bad case of featuritis.
  76    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  77
  78Very true...
  79
  80cryptpw was in bbox before this gem, so we retain it, and alias mkpasswd
  81to cryptpw. -a option (alias for -m) came from cryptpw.
  82*/
  83
  84int cryptpw_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  85int cryptpw_main(int argc UNUSED_PARAM, char **argv)
  86{
  87        /* Supports: cryptpw -m sha256 PASS 'rounds=999999999$SALT' */
  88        char salt[MAX_PW_SALT_LEN + sizeof("rounds=999999999$")];
  89        char *salt_ptr;
  90        char *password;
  91        const char *opt_m, *opt_S;
  92        int fd;
  93
  94#if ENABLE_LONG_OPTS
  95        static const char mkpasswd_longopts[] ALIGN1 =
  96                "stdin\0"       No_argument       "s"
  97                "password-fd\0" Required_argument "P"
  98                "salt\0"        Required_argument "S"
  99                "method\0"      Required_argument "m"
 100        ;
 101#endif
 102        fd = STDIN_FILENO;
 103        opt_m = CONFIG_FEATURE_DEFAULT_PASSWD_ALGO;
 104        opt_S = NULL;
 105        /* at most two non-option arguments; -P NUM */
 106        getopt32long(argv, "^" "sP:+S:m:a:" "\0" "?2",
 107                        mkpasswd_longopts,
 108                        &fd, &opt_S, &opt_m, &opt_m
 109        );
 110        argv += optind;
 111
 112        /* have no idea how to handle -s... */
 113
 114        if (argv[0] && !opt_S)
 115                opt_S = argv[1];
 116
 117        salt_ptr = crypt_make_pw_salt(salt, opt_m);
 118        if (opt_S)
 119                /* put user's data after the "$N$" prefix */
 120                safe_strncpy(salt_ptr, opt_S, sizeof(salt) - (sizeof("$N$")-1));
 121
 122        xmove_fd(fd, STDIN_FILENO);
 123
 124        password = argv[0];
 125        if (!password) {
 126                /* Only mkpasswd, and only from tty, prompts.
 127                 * Otherwise it is a plain read. */
 128                password = (ENABLE_MKPASSWD && applet_name[0] == 'm' && isatty(STDIN_FILENO))
 129                        ? bb_ask_noecho_stdin("Password: ")
 130                        : xmalloc_fgetline(stdin)
 131                ;
 132                /* may still be NULL on EOF/error */
 133        }
 134
 135        if (password)
 136                puts(pw_encrypt(password, salt, 1));
 137
 138        return EXIT_SUCCESS;
 139}
 140