[thirdparty/openssl.git] / doc / man3 / BN_security_bits.pod

=pod

=head1 NAME

BN_security_bits - returns bits of security based on given numbers

=head1 SYNOPSIS

 #include <openssl/bn.h>

 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<L> and B<N> are used to decide the bits of security, where
B<L> is the size of the public key and B<N> is the size of the private
key. For IFC, e.g., RSA, only B<L> 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 HISTORY

BN_security_bits() was added in OpenSSL 1.1.0.

=head1 SEE ALSO

L<DH_security_bits(3)>, L<DSA_security_bits(3)>, L<RSA_security_bits(3)>

=head1 COPYRIGHT

Copyright 2017 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the Apache License 2.0 (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<https://www.openssl.org/source/license.html>.

=cut
Commit	Line	Data
6a2da303 PY	1	=pod
	2
	3	=head1 NAME
	4
	5	BN_security_bits - returns bits of security based on given numbers
	6
	7	=head1 SYNOPSIS
	8
	9	#include <openssl/bn.h>
	10
	11	int BN_security_bits(int L, int N);
	12
	13	=head1 DESCRIPTION
	14
	15	BN_security_bits() returns the number of bits of security provided by a
	16	specific algorithm and a particular key size. The bits of security is
	17	defined in NIST SP800-57. Currently, BN_security_bits() support two types
	18	of asymmetric algorithms: the FFC (Finite Field Cryptography) and IFC
	19	(Integer Factorization Cryptography). For FFC, e.g., DSA and DH, both
	20	parameters B<L> and B<N> are used to decide the bits of security, where
	21	B<L> is the size of the public key and B<N> is the size of the private
	22	key. For IFC, e.g., RSA, only B<L> is used and it's commonly considered
	23	to be the key size (modulus).
	24
	25	=head1 RETURN VALUES
	26
	27	Number of security bits.
	28
	29	=head1 NOTES
	30
	31	ECC (Elliptic Curve Cryptography) is not covered by the BN_security_bits()
	32	function. The symmetric algorithms are not covered neither.
	33
	34	=head1 HISTORY
	35
	36	BN_security_bits() was added in OpenSSL 1.1.0.
	37
	38	=head1 SEE ALSO
	39
	40	L<DH_security_bits(3)>, L<DSA_security_bits(3)>, L<RSA_security_bits(3)>
	41
	42	=head1 COPYRIGHT
	43
	44	Copyright 2017 The OpenSSL Project Authors. All Rights Reserved.
	45
4746f25a	46	Licensed under the Apache License 2.0 (the "License"). You may not use
6a2da303 PY	47	this file except in compliance with the License. You can obtain a copy
	48	in the file LICENSE in the source distribution or at
	49	L<https://www.openssl.org/source/license.html>.
	50
	51	=cut