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 or an
        openssl with no-egd this function does not exist.

    random_status ()
        This function returns 1 if the PRNG has sufficient seeding. or 0 if
        not.

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).

