BN_security_bits - returns bits of security based on given numbers

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       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
       <https://www.openssl.org/source/license.html>.

3.5.0                                              2025-06-04                             BN_SECURITY_BITS(3SSL)

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 L and N are used to decide the
       bits of security, where L is the size of the public key and N is the size of the private key. For IFC,
       e.g., RSA, only L is used and it's commonly considered to be the key size (modulus).

       The BN_security_bits() function was added in OpenSSL 1.1.0.

       BN_security_bits - returns bits of security based on given numbers

       ECC (Elliptic Curve Cryptography) is not covered by the BN_security_bits() function. The symmetric
       algorithms are not covered neither.

       Number of security bits.

DH_security_bits(3), DSA_security_bits(3), RSA_security_bits(3)

        #include <openssl/bn.h>

        int BN_security_bits(int L, int N);