NAME

       Crypt::OpenSSL::Random - OpenSSL/LibreSSL pseudo-random number generator access

SYNOPSIS

         use Crypt::OpenSSL::Random;

         Crypt::OpenSSL::Random::random_seed($good_random_data);
         Crypt::OpenSSL::Random::random_egd("/tmp/entropy");
         Crypt::OpenSSL::Random::random_status() or
           die "Unable to sufficiently seed the random number generator".

         my $ten_good_random_bytes = Crypt::OpenSSL::Random::random_bytes(10);
         my $ten_ok_random_bytes = Crypt::OpenSSL::Random::random_pseudo_bytes(10);

DESCRIPTION

       "Crypt::OpenSSL::Random" provides the ability to seed and query the OpenSSL and LibreSSL library's
       pseudo-random number generators.

       Note: On LibreSSL random_egd() is not defined.

   EXPORT
       None by default.

Static Methods

       random_bytes (IV num_bytes)
           This function, returns a specified number of cryptographically strong pseudo-random bytes from the
           PRNG.  If the PRNG has not been seeded with enough randomness to ensure an unpredictable byte
           sequence, then a false value is returned.

       random_pseudo_bytes (IV num_bytes)
           This function, is similar to "random_bytes", but the resulting sequence of bytes are not necessarily
           unpredictable.  They can be used for non-cryptographic purposes and for certain purposes in
           cryptographic protocols, but usually not for key generation etc.

       random_seed (PV random_bytes_string)
           This function seeds the PRNG with a supplied string of bytes.  It returns true if the PRNG has
           sufficient seeding.  Note: calling this function with non-random bytes is of limited value at best!

       random_egd (PV egd_string)
           This function seeds the PRNG with data from the specified entropy gathering daemon.  Returns the
           number of bytes read from the daemon on success, or -1 if not enough bytes were read, or if the
           connection to the daemon failed.

           "libressl" considers this function insecure, so with libressl this function does not exist.

       random_status ()
           This function returns true if the PRNG has sufficient seeding.

BUGS

       Because of the internal workings of OpenSSL's random library, the pseudo-random number generator (PRNG)
       accessed by Crypt::OpenSSL::Random will be different than the one accessed by any other perl module.
       Hence, to use a module such as Crypt::OpenSSL::Random, you will need to seed the PRNG used there from one
       used here.  This class is still advantageous, however, as it centralizes other methods, such as
       "random_egd", in one place.

AUTHOR

       Ian Robertson, "iroberts@cpan.com"

       Now maintained by Reini Urban, "rurban@cpan.org"

LICENSE

       This module is available under the same licences as perl, the Artistic license and the GPL.

SEE ALSO

       perl(1), rand(3), RAND_add(3), RAND_egd(3), RAND_bytes(3).