feat(esp_tee): Added examples demonstrating the ESP-TEE framework

examples/security/tee/tee_attestation/main/app_main.c

@@ -0,0 +1,53 @@
+/*
+ * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include <string.h>
+#include <inttypes.h>
+#include <errno.h>
+
+#include "esp_system.h"
+#include "esp_event.h"
+#include "esp_log.h"
+#include "esp_console.h"
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+#include "esp_tee_attestation.h"
+
+static const char *TAG = "example_tee_attest";
+
+#define ESP_ATT_TK_NONCE         (0xA1B2C3D4)
+#define ESP_ATT_TK_CLIENT_ID     (0x0FACADE0)
+
+#define ESP_ATT_TK_BUF_SIZE      (1792)
+#define ESP_ATT_TK_PSA_CERT_REF  ("0716053550477-10100")
+
+static uint8_t token_buf[ESP_ATT_TK_BUF_SIZE] = {0};
+
+void app_main(void)
+{
+    ESP_LOGI(TAG, "TEE Attestation Service");
+
+    uint32_t token_len = 0;
+
+    /* Generate entity attestation token using the following parameters
+     * and return the token length in token_len:
+     * - Nonce value for freshness
+     * - Client ID to identify requester
+     * - PSA certification ID reference string
+     * - Buffer to store the generated token
+     */
+    esp_err_t err = esp_tee_att_generate_token(ESP_ATT_TK_NONCE, ESP_ATT_TK_CLIENT_ID, (const char *)ESP_ATT_TK_PSA_CERT_REF,
+                                               token_buf, sizeof(token_buf), &token_len);
+    if (err != ESP_OK) {
+        ESP_LOGE(TAG, "Failed to generate entity attestation token!");
+        abort();
+    }
+
+    /* Print the generated token details - length and contents */
+    ESP_LOGI(TAG, "Attestation token - Length: %lu", token_len);
+    ESP_LOGI(TAG, "Attestation token - Data:\n'%.*s'", (int)token_len, token_buf);
+}