BN_security_bits3ssl

Usage

 #include <openssl/bn.h>
 int BN_security_bits(int L, int N);

Overview

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).

Return values

Number of security bits.

Notes

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