NAME

       RSA_size, RSA_bits, RSA_security_bits - get RSA modulus size or security bits

SYNOPSIS

        #include <openssl/rsa.h>

        int RSA_size(const RSA *rsa);

        int RSA_bits(const RSA *rsa);

        int RSA_security_bits(const RSA *rsa)

DESCRIPTION

       RSA_size() returns the RSA modulus size in bytes. It can be used to determine how much
       memory must be allocated for an RSA encrypted value.

       RSA_bits() returns the number of significant bits.

       rsa and rsa->n must not be NULL.

       RSA_security_bits() returns the number of security bits of the given rsa key. See
       BN_security_bits(3).

RETURN VALUES

       RSA_size() returns the size of modulus in bytes.

       DSA_bits() returns the number of bits in the key.

       RSA_security_bits() returns the number of security bits.

SEE ALSO

       BN_num_bits(3)

HISTORY

       RSA_bits() was added in OpenSSL 1.1.0.

COPYRIGHT

       Copyright 2000-2018 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 <https://www.openssl.org/source/license.html>.