NAME
    App::bmkpasswd - bcrypt-capable mkpasswd(1) and exported helpers

SYNOPSIS
      ## From Perl:

      use App::bmkpasswd 'mkpasswd', 'passwdcmp';
      my $bcrypted = mkpasswd($passwd);
      say 'matched' if passwdcmp($passwd, $bcrypted);

      ## From a shell:

      bmkpasswd --help
  
      # Generate bcrypted passwords
      # Defaults to work cost factor '08':
      bmkpasswd
      bmkpasswd --workcost='06'

      # SHA requires Crypt::Passwd::XS or glibc2.7+
      bmkpasswd --method='sha512'
  
      # Compare a hash:
      bmkpasswd --check=HASH

      # Check hash generation times:
      bmkpasswd --benchmark

DESCRIPTION
    App::bmkpasswd is a simple bcrypt-enabled mkpasswd.

    Helper functions are also exported for use in other applications; see
    "EXPORTED". Crypt::Bcrypt::Easy provides an easier bcrypt-specific
    programmatic interface for Perl programmers.

    See "bmkpasswd --help" for usage information.

    Uses Crypt::Eksblowfish::Bcrypt for bcrypted passwords.

    Bcrypt comes with a configurable work-cost factor; that allows hash
    generation to become configurably slower as computers get faster,
    thereby impeding brute-force hash generation attempts.

    See <http://codahale.com/how-to-safely-store-a-password/> for more on
    why you ought to be using bcrypt or similar "adaptive" techniques.

    SHA-256 and SHA-512 are supported if available. You'll need either
    Crypt::Passwd::XS or a system crypt() that can handle SHA, such as
    glibc-2.7+ or modern FreeBSD builds.

    Uses Bytes::Random::Secure to generate random salts. For the paranoid,
    constant time comparison is used when comparing hashes; strongly-random
    salts can also be enabled.

EXPORTED
    Crypt::Bcrypt::Easy provides an easier programmatic interface, if you're
    only interested in generating bcrypt passwords. If you'd like to make
    use of other password types, you can use the exported mkpasswd and
    passwdcmp functions:

      use App::bmkpasswd 'mkpasswd', 'passwdcmp';
      # Same as:
      use App::bmkpasswd -all;

    This module uses Exporter::Tiny to export functions. This provides for
    flexible import options. See the Exporter::Tiny docs for details.

  mkpasswd
      ## Generate a bcrypted passwd with work-cost 08:
      $bcrypted = mkpasswd($passwd);

      ## Generate a bcrypted passwd with other work-cost:
      $bcrypted = mkpasswd($passwd, 'bcrypt', '10');

      ## SHA:
      $crypted = mkpasswd($passwd, 'sha256');
      $crypted = mkpasswd($passwd, 'sha512');

      ## Use a strongly-random salt (requires spare entropy):
      $crypted = mkpasswd($passwd, 'bcrypt', '08', 'strong');
      $crypted = mkpasswd($passwd, 'sha512', 0, 'strong');

  passwdcmp
      ## Compare a password against a hash
      ## passwdcmp() will return the hash if it is a match
      if ( passwdcmp($plaintext, $crypted) ) {
        ## Successful match
      } else {
        ## Failed match
      }

BUGS
    There is currently no easy way to pass your own salt; frankly, this
    thing is aimed at some projects of mine where that issue is unlikely to
    come up and randomized is appropriate. If that's a problem, patches
    welcome? ;-)

AUTHOR
    Jon Portnoy <avenj@cobaltirc.org>