| /* |
| * Copyright (c) 2017 Intel Corporation. |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| #include <drivers/entropy.h> |
| #include <ztest.h> |
| |
| /* |
| * @addtogroup t_entropy_api |
| * @{ |
| * @defgroup t_entropy_get_entropy test_entropy_get_entropy |
| * @brief TestPurpose: verify Get entropy works |
| * @details |
| * - Test Steps |
| * -# Read random numbers from Entropy driver. |
| * -# Verify whether buffer overflow occurred or not. |
| * -# Verify whether buffer completely filled or not. |
| * - Expected Results |
| * -# Random number should be generated. |
| * @} |
| */ |
| |
| #define BUFFER_LENGTH 10 |
| #define RECHECK_RANDOM_ENTROPY 0x10 |
| |
| static int random_entropy(const struct device *dev, char *buffer, char num) |
| { |
| int ret, i; |
| int count = 0; |
| |
| (void)memset(buffer, num, BUFFER_LENGTH); |
| |
| /* The BUFFER_LENGTH-1 is used so the driver will not |
| * write the last byte of the buffer. If that last |
| * byte is not 0 on return it means the driver wrote |
| * outside the passed buffer, and that should never |
| * happen. |
| */ |
| ret = entropy_get_entropy(dev, buffer, BUFFER_LENGTH - 1); |
| if (ret) { |
| TC_PRINT("Error: entropy_get_entropy failed: %d\n", ret); |
| return TC_FAIL; |
| } |
| if (buffer[BUFFER_LENGTH - 1] != num) { |
| TC_PRINT("Error: entropy_get_entropy buffer overflow\n"); |
| return TC_FAIL; |
| } |
| |
| for (i = 0; i < BUFFER_LENGTH - 1; i++) { |
| TC_PRINT(" 0x%02x\n", buffer[i]); |
| if (buffer[i] == num) { |
| count++; |
| } |
| } |
| |
| if (count >= 2) { |
| return RECHECK_RANDOM_ENTROPY; |
| } else { |
| return TC_PASS; |
| } |
| } |
| |
| /* |
| * Function invokes the get_entropy callback in driver |
| * to get the random data and fill to passed buffer |
| */ |
| static int get_entropy(void) |
| { |
| const struct device *dev; |
| uint8_t buffer[BUFFER_LENGTH] = { 0 }; |
| int ret; |
| |
| dev = device_get_binding(DT_CHOSEN_ZEPHYR_ENTROPY_LABEL); |
| if (!dev) { |
| TC_PRINT("error: no random device\n"); |
| return TC_FAIL; |
| } |
| |
| TC_PRINT("random device is %p, name is %s\n", |
| dev, dev->name); |
| |
| ret = random_entropy(dev, buffer, 0); |
| |
| /* Check whether 20% or more of buffer still filled with default |
| * value(0), if yes then recheck again by filling nonzero value(0xa5) |
| * to buffer. Recheck random_entropy and verify whether 20% or more |
| * of buffer filled with value(0xa5) or not. |
| */ |
| if (ret == RECHECK_RANDOM_ENTROPY) { |
| ret = random_entropy(dev, buffer, 0xa5); |
| if (ret == RECHECK_RANDOM_ENTROPY) { |
| return TC_FAIL; |
| } else { |
| return ret; |
| } |
| } |
| return ret; |
| } |
| |
| static void test_entropy_get_entropy(void) |
| { |
| zassert_true(get_entropy() == TC_PASS, NULL); |
| } |
| |
| void test_main(void) |
| { |
| ztest_test_suite(entropy_api, |
| ztest_unit_test(test_entropy_get_entropy)); |
| ztest_run_test_suite(entropy_api); |
| } |