Crypt::OpenSSL::Random - OpenSSL/LibreSSL pseudo-random number generator access
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
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 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
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, "email@example.com"
Now maintained by Reini Urban, "firstname.lastname@example.org"
This module is available under the same licences as perl, the Artistic license
and the GPL.