Crypt::OpenSSL::Random - OpenSSL/LibreSSL pseudo-random number generator access
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);
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.
None by default.
- 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.
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.
Ian Robertson, iroberts@cpan.com
Now maintained by Reini Urban, rurban@cpan.org
This module is available under the same licences as perl, the Artistic
license and the GPL.
perl(1), rand(3), RAND_add(3), RAND_egd(3), RAND_bytes(3).
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