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 c<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).

perl v5.22.1                                       2015-12-17                                        Random(3pm)