fn from_ec_private_bn()

in aws-lc-rs/src/ec/encoding.rs [92:132]

• 36 lines of code
• 6 McCabe index (conditional complexity)

    fn from_ec_private_bn(
        ec_group: &ConstPointer<EC_GROUP>,
        private_big_num: &ConstPointer<BIGNUM>,
    ) -> Result<LcPtr<EVP_PKEY>, KeyRejected> {
        let ec_key = DetachableLcPtr::new(unsafe { EC_KEY_new() })?;
        if 1 != unsafe { EC_KEY_set_group(*ec_key, **ec_group) } {
            return Err(KeyRejected::unexpected_error());
        }
        if 1 != unsafe { EC_KEY_set_private_key(*ec_key, **private_big_num) } {
            return Err(KeyRejected::invalid_encoding());
        }
        let mut pub_key = LcPtr::new(unsafe { EC_POINT_new(**ec_group) })?;
        if 1 != unsafe {
            EC_POINT_mul(
                **ec_group,
                *pub_key.as_mut(),
                **private_big_num,
                null(),
                null(),
                null_mut(),
            )
        } {
            return Err(KeyRejected::unexpected_error());
        }
        if 1 != unsafe { EC_KEY_set_public_key(*ec_key, *pub_key.as_const()) } {
            return Err(KeyRejected::unexpected_error());
        }
        let expected_curve_nid = unsafe { EC_GROUP_get_curve_name(**ec_group) };

        let mut pkey = LcPtr::new(unsafe { EVP_PKEY_new() })?;

        if 1 != unsafe { EVP_PKEY_assign_EC_KEY(*pkey.as_mut(), *ec_key) } {
            return Err(KeyRejected::unexpected_error());
        }
        ec_key.detach();

        // Validate the EC_KEY before returning it.
        validate_ec_evp_key(&pkey.as_const(), expected_curve_nid)?;

        Ok(pkey)
    }