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✏️ Editing: BN_security_bits.3

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.\"
.IX Title "BN_SECURITY_BITS 3"
.TH BN_SECURITY_BITS 3 "2023-09-11" "1.1.1w" "OpenSSL"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
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.nh
.SH "NAME"
BN_security_bits \- returns bits of security based on given numbers
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\& #include <openssl/bn.h>
\&
\& int BN_security_bits(int L, int N);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\fBBN_security_bits()\fR returns the number of bits of security provided by a
specific algorithm and a particular key size. The bits of security is
defined in \s-1NIST SP800\-57.\s0 Currently, \fBBN_security_bits()\fR support two types
of asymmetric algorithms: the \s-1FFC\s0 (Finite Field Cryptography) and \s-1IFC\s0
(Integer Factorization Cryptography). For \s-1FFC,\s0 e.g., \s-1DSA\s0 and \s-1DH,\s0 both
parameters \fBL\fR and \fBN\fR are used to decide the bits of security, where
\&\fBL\fR is the size of the public key and \fBN\fR is the size of the private
key. For \s-1IFC,\s0 e.g., \s-1RSA,\s0 only \fBL\fR is used and it's commonly considered
to be the key size (modulus).
.SH "RETURN VALUES"
.IX Header "RETURN VALUES"
Number of security bits.
.SH "NOTES"
.IX Header "NOTES"
\&\s-1ECC\s0 (Elliptic Curve Cryptography) is not covered by the \fBBN_security_bits()\fR
function. The symmetric algorithms are not covered neither.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fBDH_security_bits\fR\|(3), \fBDSA_security_bits\fR\|(3), \fBRSA_security_bits\fR\|(3)
.SH "HISTORY"
.IX Header "HISTORY"
The \fBBN_security_bits()\fR function was added in OpenSSL 1.1.0.
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright 2017\-2019 The OpenSSL Project Authors. All Rights Reserved.
.PP
Licensed under the OpenSSL license (the \*(L"License\*(R").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file \s-1LICENSE\s0 in the source distribution or at
<https://www.openssl.org/source/license.html>.

MR SKB