=pod
=head1 NAME
BN_security_bits - returns bits of security based on given numbers
=head1 SYNOPSIS
#include
int BN_security_bits(int L, int N);
=head1 DESCRIPTION
BN_security_bits() returns the number of bits of security provided by a
specific algorithm and a particular key size. The bits of security is
defined in NIST SP800-57. Currently, BN_security_bits() support two types
of asymmetric algorithms: the FFC (Finite Field Cryptography) and IFC
(Integer Factorization Cryptography). For FFC, e.g., DSA and DH, both
parameters B and B are used to decide the bits of security, where
B is the size of the public key and B is the size of the private
key. For IFC, e.g., RSA, only B is used and it's commonly considered
to be the key size (modulus).
=head1 RETURN VALUES
Number of security bits.
=head1 NOTES
ECC (Elliptic Curve Cryptography) is not covered by the BN_security_bits()
function. The symmetric algorithms are not covered neither.
=head1 SEE ALSO
L, L, L
=head1 HISTORY
The BN_security_bits() function was added in OpenSSL 1.1.0.
=head1 COPYRIGHT
Copyright 2017-2019 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the OpenSSL license (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
L.
=cut