safe_BN_num_bits
n = safe_BN_num_bits(RSA_get0_n(r));
if (safe_BN_num_bits(RSA_get0_d(r)) > n)
bits = safe_BN_num_bits(sk_BIGNUM_const_value(exps, i));
bits = safe_BN_num_bits(sk_BIGNUM_const_value(factors, i));
bits = safe_BN_num_bits(sk_BIGNUM_const_value(coeffs, i));