csrng_testutils.h

// Copyright lowRISC contributors (OpenTitan project).
// Licensed under the Apache License, Version 2.0, see LICENSE for details.
// SPDX-License-Identifier: Apache-2.0
 
#ifndef OPENTITAN_SW_DEVICE_LIB_TESTING_CSRNG_TESTUTILS_H_
#define OPENTITAN_SW_DEVICE_LIB_TESTING_CSRNG_TESTUTILS_H_
 
#include "sw/device/lib/base/status.h"
#include "sw/device/lib/dif/dif_csrng.h"
#include "sw/device/lib/dif/dif_csrng_shared.h"
 
/**
 * Generates randomized seed material.
 *
 * @param disable_rand If set, the generated seed material has length zero.
 * @param seed_material The seed material to generate.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_seed_material_build(
    bool disable_rand, dif_csrng_seed_material_t *seed_material);
 
/**
 * Returns a randomized CSRNG application command.
 *
 * @param disable_rand If set, a struct containing default values is returned.
 * @param id CSRNG application command to generate.
 * @param entropy_src_en If set, Instantiate and Reseed commands use entropy
 * from the entropy source.
 * @param glen_val If > 0, the generate length is set to glen_val.
 * @param seed_material The seed material to generate and use for the generated
 * application command.
 * @return The generated CSRNG application command.
 */
OT_WARN_UNUSED_RESULT
csrng_app_cmd_t csrng_testutils_app_cmd_build(
    bool disable_rand, csrng_app_cmd_id_t id,
    dif_csrng_entropy_src_toggle_t entropy_src_en, unsigned int glen_val,
    dif_csrng_seed_material_t *seed_material);
 
/**
 * Wait for the `csrng` instance command interface to be ready to accept
 * commands. Aborts test execution if an error is found.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_cmd_ready_wait(const dif_csrng_t *csrng);
 
/**
 * Runs CSRNG generate command.
 *
 * @param csrng A CSRNG handle.
 * @param output Output buffer.
 * @param output_len Number of words of entropy to write to output buffer.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_cmd_generate_run(const dif_csrng_t *csrng,
                                          uint32_t *output, size_t output_len);
 
/**
 * Checks the CSRNG internal state against `expected` values.
 *
 * @param csrng A CSRNG handle.
 * @param expected Expected CSRNG internal state.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_check_internal_state(
    const dif_csrng_t *csrng, const dif_csrng_internal_state_t *expected);
 
/**
 * CTR_DRBG Known-Answer-Test (KAT) for INSTANTIATE command.
 *
 * @param csrng A CSRNG handle.
 * @param fail_expected Expected fail.
 * @param seed_material Seed material to use for the command.
 * @param expected_state Expected CSRNG internal state after the command.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_kat_instantiate(
    const dif_csrng_t *csrng, bool fail_expected,
    const dif_csrng_seed_material_t *seed_material,
    const dif_csrng_internal_state_t *expected_state);
 
/**
 * CTR_DRBG Known-Answer-Test (KAT) for GENERATE command.
 *
 * @param csrng A CSRNG handle.
 * @param num_generates Number of GENERATE commands to run.
 * @param output_len Number of output words to read from CSRNG after the last
 * command.
 * @param expected_output Expected CSRNG output after the last command.
 * @param expected_state Expected CSRNG internal state after the last command.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_kat_generate(
    const dif_csrng_t *csrng, uint32_t num_generates, uint32_t output_len,
    const uint32_t *expected_output,
    const dif_csrng_internal_state_t *expected_state);
 
/**
 * CTR_DRBG Known-Answer-Test (KAT) for RESEED command.
 *
 * @param csrng A CSRNG handle.
 * @param seed_material Seed material to use for the command.
 * @param expected_state Expected CSRNG internal state after the command.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_kat_reseed(
    const dif_csrng_t *csrng, const dif_csrng_seed_material_t *seed_material,
    const dif_csrng_internal_state_t *expected_state);
 
/**
 * CTR DRBG Known-Answer-Test (KAT) for INSTANTIATE command.
 *
 * @param csrng Handle.
 * @param fail_expected Expected fail.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_fips_instantiate_kat(const dif_csrng_t *csrng,
                                              bool fail_expected);
 
/**
 * CTR DRBG Known-Answer-Test (KAT) for GENERATE command.
 *
 * @param csrng Handle.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_fips_generate_kat(const dif_csrng_t *csrng);
 
/**
 * Checks CSRNG command status.
 *
 * Asserts error if the command or internal FIFO status contains any errors.
 *
 * @param csrng Handle.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_cmd_status_check(const dif_csrng_t *csrng);
 
/**
 * Checks CSRNG recoverable alerts.
 *
 * Asserts error if there are any CSRNG recoverable alerts set.
 *
 * @param csrng Handle.
 */
OT_WARN_UNUSED_RESULT
status_t csrng_testutils_recoverable_alerts_check(const dif_csrng_t *csrng);
 
#endif  // OPENTITAN_SW_DEVICE_LIB_TESTING_CSRNG_TESTUTILS_H_