esp32h2: add secure boot feature support

Closes IDF-6281

components/app_update/esp_ota_ops.c

@@ -43,6 +43,8 @@
 #include "esp32c2/rom/secure_boot.h"
 #elif CONFIG_IDF_TARGET_ESP32C6
 #include "esp32c6/rom/secure_boot.h"
+#elif CONFIG_IDF_TARGET_ESP32H2
+#include "esp32h2/rom/secure_boot.h"
 #endif
 
 #define SUB_TYPE_ID(i) (i & 0x0F)

components/bootloader_support/src/esp32h2/bootloader_sha.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -24,7 +24,11 @@ bootloader_sha256_handle_t bootloader_sha256_start()
 void bootloader_sha256_data(bootloader_sha256_handle_t handle, const void *data, size_t data_len)
 {
     assert(handle != NULL);
-    assert(data_len % 4 == 0);
+    /* H2 secure boot key field consists of 1 byte of curve identifier and 64 bytes of ECDSA public key.
+     * While verifying the signature block, we need to calculate the SHA of this key field which is of 65 bytes.
+     * ets_sha_update handles it cleanly so we can safely remove the check:
+     * assert(data_len % 4) == 0
+     */
     ets_sha_update(&ctx, data, data_len, false);
 }
 

components/bootloader_support/src/secure_boot_v2/secure_boot.c

@@ -14,22 +14,8 @@
 #include "esp_image_format.h"
 #include "esp_efuse.h"
 #include "esp_efuse_table.h"
+#include "secure_boot_signature_priv.h"
 
-#if CONFIG_IDF_TARGET_ESP32
-#include "esp32/rom/secure_boot.h"
-#elif CONFIG_IDF_TARGET_ESP32S2
-#include "esp32s2/rom/secure_boot.h"
-#elif CONFIG_IDF_TARGET_ESP32C3
-#include "esp32c3/rom/secure_boot.h"
-#elif CONFIG_IDF_TARGET_ESP32S3
-#include "esp32s3/rom/secure_boot.h"
-#elif CONFIG_IDF_TARGET_ESP32H4
-#include "esp32h4/rom/secure_boot.h"
-#elif CONFIG_IDF_TARGET_ESP32C2
-#include "esp32c2/rom/secure_boot.h"
-#elif CONFIG_IDF_TARGET_ESP32C6
-#include "esp32c6/rom/secure_boot.h"
-#endif
 
 /* The following API implementations are used only when called
  * from the bootloader code.

components/bootloader_support/src/secure_boot_v2/secure_boot_signature_priv.h

@@ -19,6 +19,8 @@
 #include "esp32c2/rom/secure_boot.h"
 #elif CONFIG_IDF_TARGET_ESP32C6
 #include "esp32c6/rom/secure_boot.h"
+#elif CONFIG_IDF_TARGET_ESP32H2
+#include "esp32h2/rom/secure_boot.h"
 #endif
 
 esp_err_t verify_ecdsa_signature_block(const ets_secure_boot_signature_t *sig_block, const uint8_t *image_digest, const ets_secure_boot_sig_block_t *trusted_block);

components/esp_rom/include/esp32h2/rom/ecdsa.h

@@ -0,0 +1,26 @@
+/*
+ * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define ETS_DIGEST_LEN 32 /* SHA-256, bytes */
+
+typedef enum {
+    ECDSA_CURVE_P192 = 1,
+    ECDSA_CURVE_P256 = 2
+} ECDSA_CURVE;
+
+int ets_ecdsa_verify(const uint8_t *key, const uint8_t *sig, ECDSA_CURVE curve_id, const uint8_t *digest, uint8_t *verified_digest);
+
+#ifdef __cplusplus
+}
+#endif

components/esp_rom/include/esp32h2/rom/secure_boot.h

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -9,6 +9,7 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include "ets_sys.h"
+#include "ecdsa.h"
 #include "rsa_pss.h"
 #include "esp_assert.h"
 
@@ -16,6 +17,8 @@
 extern "C" {
 #endif
 
+#if CONFIG_SECURE_BOOT_V2_ENABLED || CONFIG_SECURE_SIGNED_APPS_NO_SECURE_BOOT
+
 typedef struct ets_secure_boot_sig_block ets_secure_boot_sig_block_t;
 typedef struct ets_secure_boot_signature ets_secure_boot_signature_t;
 typedef struct ets_secure_boot_key_digests ets_secure_boot_key_digests_t;
@@ -69,6 +72,8 @@ void ets_secure_boot_revoke_public_key_digest(int index);
 
    (Up to 3 in a signature sector are appended to the image)
  */
+#if CONFIG_SECURE_SIGNED_APPS_RSA_SCHEME
+
 struct ets_secure_boot_sig_block {
     uint8_t magic_byte;
     uint8_t version;
@@ -81,6 +86,27 @@ struct ets_secure_boot_sig_block {
     uint8_t _padding[16];
 };
 
+#elif CONFIG_SECURE_SIGNED_APPS_ECDSA_V2_SCHEME
+
+struct __attribute((packed)) ets_secure_boot_sig_block {
+    uint8_t magic_byte;
+    uint8_t version;
+    uint8_t _reserved1;
+    uint8_t _reserved2;
+    uint8_t image_digest[32];
+    struct {
+        struct {
+            uint8_t curve_id; /* ETS_ECDSA_CURVE_P192 / ETS_ECDSA_CURVE_P256 */
+            uint8_t point[64]; /* X followed by Y (both little-endian), plus zero bytes if P192 */
+        } key;
+        uint8_t signature[64]; /* r followed by s (both little-endian) */
+        uint8_t padding[1031];
+    } ecdsa;
+    uint32_t block_crc; /* note: crc covers all bytes in the structure before it, regardless of version field */
+    uint8_t _padding[16];
+};
+#endif
+
 ESP_STATIC_ASSERT(sizeof(ets_secure_boot_sig_block_t) == 1216, "invalid sig block size");
 
 #define SECURE_BOOT_NUM_BLOCKS 3
@@ -100,6 +126,8 @@ struct ets_secure_boot_key_digests {
     bool allow_key_revoke;
 };
 
+#endif /* CONFIG_SECURE_BOOT_V2_ENABLED || CONFIG_SECURE_SIGNED_APPS_NO_SECURE_BOOT */
+
 #ifdef __cplusplus
 }
 #endif