esp32h2: add DS peripheral HAL

components/hal/esp32h2/include/hal/ds_ll.h

@@ -0,0 +1,167 @@
+/*
+ * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/*******************************************************************************
+ * NOTICE
+ * The hal is not public api, don't use it in application code.
+ ******************************************************************************/
+
+#pragma once
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
+
+#include "soc/hwcrypto_reg.h"
+#include "soc/soc_caps.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+static inline void ds_ll_start(void)
+{
+    REG_WRITE(DS_SET_START_REG, 1);
+}
+
+/**
+ * @brief Wait until DS peripheral has finished any outstanding operation.
+ */
+static inline bool ds_ll_busy(void)
+{
+    return (REG_READ(DS_QUERY_BUSY_REG) > 0) ? true : false;
+}
+
+/**
+ * @brief Busy wait until the hardware is ready.
+ */
+static inline void ds_ll_wait_busy(void)
+{
+    while (ds_ll_busy());
+}
+
+/**
+ * @brief In case of a key error, check what caused it.
+ */
+static inline ds_key_check_t ds_ll_key_error_source(void)
+{
+    uint32_t key_error = REG_READ(DS_QUERY_KEY_WRONG_REG);
+    if (key_error == 0) {
+        return DS_NO_KEY_INPUT;
+    } else {
+        return DS_OTHER_WRONG;
+    }
+}
+
+/**
+ * @brief Write the initialization vector to the corresponding register field.
+ */
+static inline void ds_ll_configure_iv(const uint32_t *iv)
+{
+    for (size_t i = 0; i < (SOC_DS_KEY_PARAM_MD_IV_LENGTH / sizeof(uint32_t)); i++) {
+        REG_WRITE(DS_IV_MEM + (i * 4) , iv[i]);
+    }
+}
+
+/**
+ * @brief Write the message which should be signed.
+ *
+ * @param msg Pointer to the message.
+ * @param size Length of msg in bytes. It is the RSA signature length in bytes.
+ */
+static inline void ds_ll_write_message(const uint8_t *msg, size_t size)
+{
+    memcpy((uint8_t*) DS_X_MEM, msg, size);
+    asm volatile ("fence");
+}
+
+/**
+ * @brief Write the encrypted private key parameters.
+ */
+static inline void ds_ll_write_private_key_params(const uint8_t *encrypted_key_params)
+{
+    /* Note: as the internal peripheral still has RSA 4096 structure,
+       but C is encrypted based on the actual max RSA length (ETS_DS_MAX_BITS), need to fragment it
+       when copying to hardware...
+
+       (note if ETS_DS_MAX_BITS == 4096, this should be the same as copying data->c to hardware in one fragment)
+    */
+    typedef struct { uint32_t addr; size_t len; } frag_t;
+    const frag_t frags[] = {
+                            {DS_Y_MEM,  SOC_DS_SIGNATURE_MAX_BIT_LEN / 8},
+                            {DS_M_MEM,  SOC_DS_SIGNATURE_MAX_BIT_LEN / 8},
+                            {DS_RB_MEM, SOC_DS_SIGNATURE_MAX_BIT_LEN / 8},
+                            {DS_BOX_MEM, DS_IV_MEM - DS_BOX_MEM},
+    };
+    const size_t NUM_FRAGS = sizeof(frags)/sizeof(frag_t);
+    const uint8_t *from = encrypted_key_params;
+
+    for (int i = 0; i < NUM_FRAGS; i++) {
+        memcpy((uint8_t *)frags[i].addr, from, frags[i].len);
+        asm volatile ("fence");
+        from += frags[i].len;
+    }
+}
+
+/**
+ * @brief Begin signing procedure.
+ */
+static inline void ds_ll_start_sign(void)
+{
+    REG_WRITE(DS_SET_CONTINUE_REG, 1);
+}
+
+/**
+ * @brief check the calculated signature.
+ *
+ * @return
+ * - DS_SIGNATURE_OK if no issue is detected with the signature.
+ * - DS_SIGNATURE_PADDING_FAIL if the padding of the private key parameters is wrong.
+ * - DS_SIGNATURE_MD_FAIL if the message digest check failed. This means that the message digest calculated using
+ *      the private key parameters fails, i.e., the integrity of the private key parameters is not protected.
+ * - DS_SIGNATURE_PADDING_AND_MD_FAIL if both padding and message digest check fail.
+ */
+static inline ds_signature_check_t ds_ll_check_signature(void)
+{
+    uint32_t result = REG_READ(DS_QUERY_CHECK_REG);
+    switch(result) {
+    case 0:
+        return DS_SIGNATURE_OK;
+    case 1:
+        return DS_SIGNATURE_MD_FAIL;
+    case 2:
+        return DS_SIGNATURE_PADDING_FAIL;
+    default:
+        return DS_SIGNATURE_PADDING_AND_MD_FAIL;
+    }
+}
+
+/**
+ * @brief Read the signature from the hardware.
+ *
+ * @param result The signature result.
+ * @param size Length of signature result in bytes. It is the RSA signature length in bytes.
+ */
+static inline void ds_ll_read_result(uint8_t *result, size_t size)
+{
+    memcpy(result, (uint8_t*) DS_Z_MEM, size);
+    asm volatile ("fence");
+}
+
+/**
+ * @brief Exit the signature operation.
+ *
+ * @note This does not deactivate the module. Corresponding clock/reset bits have to be triggered for deactivation.
+ */
+static inline void ds_ll_finish(void)
+{
+    REG_WRITE(DS_SET_FINISH_REG, 1);
+    ds_ll_wait_busy();
+}
+
+#ifdef __cplusplus
+}
+#endif