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xiaoxiang pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/incubator-nuttx.git
commit 9e5e60ba4893b22f6bc6289a734415c365712461
Author: Gustavo Henrique Nihei <gustavo.ni...@espressif.com>
AuthorDate: Thu Dec 30 11:58:24 2021 -0300
esp32s2/esp32c3: Build MCUboot bootloader with Flash Encryption support
---
arch/risc-v/src/esp32c3/Bootloader.mk | 7 +++
arch/risc-v/src/esp32c3/Kconfig | 2 +
arch/risc-v/src/esp32c3/Kconfig.security | 94 ++++++++++++++++++++++++++++++--
arch/xtensa/src/esp32/Kconfig.security | 4 +-
arch/xtensa/src/esp32s2/Bootloader.mk | 7 +++
arch/xtensa/src/esp32s2/Kconfig | 10 ++++
arch/xtensa/src/esp32s2/Kconfig.security | 94 ++++++++++++++++++++++++++++++--
tools/esp32s2/Config.mk | 2 +-
8 files changed, 209 insertions(+), 11 deletions(-)
diff --git a/arch/risc-v/src/esp32c3/Bootloader.mk
b/arch/risc-v/src/esp32c3/Bootloader.mk
index 5211259..ba39945 100644
--- a/arch/risc-v/src/esp32c3/Bootloader.mk
+++ b/arch/risc-v/src/esp32c3/Bootloader.mk
@@ -78,7 +78,14 @@ ifeq ($(CONFIG_ESP32C3_APP_FORMAT_MCUBOOT),y)
$(if $(CONFIG_ESP32C3_SECURE_BOOT_ALLOW_JTAG),$(call
cfg_en,CONFIG_SECURE_BOOT_ALLOW_JTAG)) \
$(if $(CONFIG_ESP32C3_SECURE_BOOT_ALLOW_EFUSE_RD_DIS),$(call
cfg_en,CONFIG_SECURE_BOOT_V2_ALLOW_EFUSE_RD_DIS)) \
$(if $(CONFIG_ESP32C3_SECURE_DISABLE_ROM_DL_MODE),$(call
cfg_en,CONFIG_SECURE_DISABLE_ROM_DL_MODE)) \
+ $(if $(CONFIG_ESP32C3_SECURE_ENABLE_SECURE_ROM_DL_MODE),$(call
cfg_en,CONFIG_SECURE_ENABLE_SECURE_ROM_DL_MODE)) \
$(if $(CONFIG_ESP32C3_SECURE_INSECURE_ALLOW_DL_MODE),$(call
cfg_en,CONFIG_SECURE_INSECURE_ALLOW_DL_MODE)) \
+ $(if $(CONFIG_ESP32C3_SECURE_FLASH_ENC_ENABLED),$(call
cfg_en,CONFIG_SECURE_FLASH_ENC_ENABLED)) \
+ $(if
$(CONFIG_ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT),$(call
cfg_en,CONFIG_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT)) \
+ $(if
$(CONFIG_ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_RELEASE),$(call
cfg_en,CONFIG_SECURE_FLASH_ENCRYPTION_MODE_RELEASE)) \
+ $(if
$(CONFIG_ESP32C3_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC),$(call
cfg_en,CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC)) \
+ $(if
$(CONFIG_ESP32C3_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE),$(call
cfg_en,CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE)) \
+ $(if
$(CONFIG_ESP32C3_SECURE_FLASH_REQUIRE_ALREADY_ENABLED),$(call
cfg_en,CONFIG_SECURE_FLASH_REQUIRE_ALREADY_ENABLED)) \
$(call cfg_val,CONFIG_ESP_BOOTLOADER_SIZE,0xF000) \
$(call
cfg_val,CONFIG_ESP_APPLICATION_PRIMARY_START_ADDRESS,$(CONFIG_ESP32C3_OTA_PRIMARY_SLOT_OFFSET))
\
$(call
cfg_val,CONFIG_ESP_APPLICATION_SIZE,$(CONFIG_ESP32C3_OTA_SLOT_SIZE)) \
diff --git a/arch/risc-v/src/esp32c3/Kconfig b/arch/risc-v/src/esp32c3/Kconfig
index a8356bb..7b3cdd1 100644
--- a/arch/risc-v/src/esp32c3/Kconfig
+++ b/arch/risc-v/src/esp32c3/Kconfig
@@ -77,6 +77,8 @@ config ESP32C3_ESPTOOLPY_NO_STUB
The flasher tool sends a precompiled download stub first by
default.
That stub allows things like compressed downloads and more.
Usually you should not need to disable that feature.
+ It is only required to be disabled in certain scenarios when
either
+ Secure Boot V2 or Flash Encryption is enabled.
config ESP32C3_FLASH_DETECT
bool "Auto-detect FLASH size"
diff --git a/arch/risc-v/src/esp32c3/Kconfig.security
b/arch/risc-v/src/esp32c3/Kconfig.security
index d4876bd..250e33c 100644
--- a/arch/risc-v/src/esp32c3/Kconfig.security
+++ b/arch/risc-v/src/esp32c3/Kconfig.security
@@ -21,7 +21,7 @@ config ESP32C3_SECURE_BOOT
if ESP32C3_SECURE_BOOT
-comment "Secure Boot support requires building bootloader from source
(ESP32C3_BOOTLOADER_BUILD_FROM_SOURCE)"
+comment "Secure Boot support requires building the bootloader from source
(ESP32C3_BOOTLOADER_BUILD_FROM_SOURCE)"
depends on !ESP32C3_BOOTLOADER_BUILD_FROM_SOURCE
config ESP32C3_SECURE_BOOT_BUILD_SIGNED_BINARIES
@@ -101,8 +101,54 @@ config ESP32C3_SECURE_BOOT_INSECURE
endif # ESP32C3_SECURE_BOOT
+comment "Flash Encryption"
+
+config ESP32C3_SECURE_FLASH_ENC_ENABLED
+ bool "Enable Flash Encryption on boot (READ HELP FIRST)"
+ default n
+ depends on ESP32C3_APP_FORMAT_MCUBOOT
+ ---help---
+ If this option is set, flash contents will be encrypted by the
bootloader on first boot.
+
+ Note: After first boot, the system will be permanently
encrypted. Re-flashing an encrypted
+ system is complicated and not always possible.
+
+ Read
https://docs.espressif.com/projects/esp-idf/en/latest/esp32c3/security/flash-encryption.html
+ before enabling.
+
+if ESP32C3_SECURE_FLASH_ENC_ENABLED
+
+comment "Flash Encryption support requires building the bootloader from source
(ESP32C3_BOOTLOADER_BUILD_FROM_SOURCE)"
+ depends on !ESP32C3_BOOTLOADER_BUILD_FROM_SOURCE
+
+choice ESP32C3_SECURE_FLASH_ENCRYPTION_MODE
+ bool "Enable usage mode"
+ default ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ ---help---
+ By default, Development mode is enabled which allows ROM
download mode to perform Flash Encryption
+ operations (plaintext is sent to the device, and it encrypts it
internally and writes ciphertext
+ to flash). This mode is not secure, it's possible for an
attacker to write their own chosen plaintext
+ to flash.
+
+ Release mode should always be selected for production or
manufacturing. Once enabled it's no longer
+ possible for the device in ROM Download Mode to use the Flash
Encryption hardware.
+
+ Refer to the Flash Encryption section of the ESP-IDF
Programmer's Guide for details:
+
https://docs.espressif.com/projects/esp-idf/en/latest/esp32c3/security/flash-encryption.html#flash-encryption-configuration
+
+ config ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ bool "Development (NOT SECURE)"
+ select ESP32C3_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC
+
+ config ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_RELEASE
+ bool "Release"
+
+endchoice
+
+endif # ESP32C3_SECURE_FLASH_ENC_ENABLED
+
menu "Potentially insecure options"
- visible if ESP32C3_SECURE_BOOT_INSECURE
+ visible if ESP32C3_SECURE_BOOT_INSECURE ||
ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
# NOTE: Options in this menu NEED to have ESP32C3_SECURE_BOOT_INSECURE
# and/or ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT in "depends
on", as the menu
@@ -113,7 +159,7 @@ menu "Potentially insecure options"
config ESP32C3_SECURE_BOOT_ALLOW_JTAG
bool "Allow JTAG Debugging"
default n
- depends on ESP32C3_SECURE_BOOT_INSECURE
+ depends on ESP32C3_SECURE_BOOT_INSECURE ||
ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
---help---
If not set (default), the bootloader will permanently disable
JTAG (across entire chip) on first boot
when either Secure Boot or Flash Encryption is enabled.
@@ -143,12 +189,51 @@ config ESP32C3_SECURE_BOOT_ALLOW_EFUSE_RD_DIS
then it is __NOT__ possible to read/write efuses using
espefuse.py utility.
However, efuse can be read/written from the application.
+config ESP32C3_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC
+ bool "Leave UART bootloader encryption enabled"
+ default n
+ depends on ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ ---help---
+ If not set (default), the bootloader will permanently disable
UART bootloader encryption access on
+ first boot. If set, the UART bootloader will still be able to
access hardware encryption.
+
+ It is recommended to only set this option in testing
environments.
+
+config ESP32C3_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE
+ bool "Leave UART bootloader flash cache enabled"
+ default n
+ depends on ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ ---help---
+ If not set (default), the bootloader will permanently disable
UART bootloader flash cache access on
+ first boot. If set, the UART bootloader will still be able to
access the flash cache.
+
+ Only set this option in testing environments.
+
+config ESP32C3_SECURE_FLASH_REQUIRE_ALREADY_ENABLED
+ bool "Require Flash Encryption to be already enabled"
+ default n
+ depends on ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ ---help---
+ If not set (default), and Flash Encryption is not yet enabled
in eFuses, the 2nd stage bootloader
+ will enable Flash Encryption: generate the Flash Encryption key
and program eFuses.
+ If this option is set, and Flash Encryption is not yet enabled,
the bootloader will error out and
+ reboot.
+ If Flash Encryption is enabled in eFuses, this option does not
change the bootloader behavior.
+
+ Only use this option in testing environments, to avoid
accidentally enabling Flash Encryption on
+ the wrong device. The device needs to have Flash Encryption
already enabled using espefuse.py.
+
endmenu # Potentially insecure options
+config ESP32C3_SECURE_ROM_DL_MODE_ENABLED
+ bool
+ default y if !ESP32C3_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+
choice ESP32C3_SECURE_UART_ROM_DL_MODE
bool "UART ROM download mode"
+ default ESP32C3_SECURE_ENABLE_SECURE_ROM_DL_MODE if
ESP32C3_SECURE_ROM_DL_MODE_ENABLED
default ESP32C3_SECURE_INSECURE_ALLOW_DL_MODE
- depends on ESP32C3_SECURE_BOOT
+ depends on ESP32C3_SECURE_BOOT || ESP32C3_SECURE_FLASH_ENC_ENABLED
config ESP32C3_SECURE_DISABLE_ROM_DL_MODE
bool "Permanently disabled (recommended)"
@@ -167,6 +252,7 @@ choice ESP32C3_SECURE_UART_ROM_DL_MODE
config ESP32C3_SECURE_ENABLE_SECURE_ROM_DL_MODE
bool "Permanently switch to Secure mode (recommended)"
+ select ESP32C3_ESPTOOLPY_NO_STUB
---help---
If set, during startup the app will burn an eFuse bit
to permanently switch the UART ROM
Download Mode into a separate Secure Download mode.
This option can only work if
diff --git a/arch/xtensa/src/esp32/Kconfig.security
b/arch/xtensa/src/esp32/Kconfig.security
index b79b2f50..1422b23 100644
--- a/arch/xtensa/src/esp32/Kconfig.security
+++ b/arch/xtensa/src/esp32/Kconfig.security
@@ -20,7 +20,7 @@ config ESP32_SECURE_BOOT
if ESP32_SECURE_BOOT
-comment "Secure Boot support requires building bootloader from source
(ESP32_BOOTLOADER_BUILD_FROM_SOURCE)"
+comment "Secure Boot support requires building the bootloader from source
(ESP32_BOOTLOADER_BUILD_FROM_SOURCE)"
depends on !ESP32_BOOTLOADER_BUILD_FROM_SOURCE
config ESP32_SECURE_BOOT_BUILD_SIGNED_BINARIES
@@ -117,7 +117,7 @@ config ESP32_SECURE_FLASH_ENC_ENABLED
if ESP32_SECURE_FLASH_ENC_ENABLED
-comment "Flash Encryption support requires building bootloader from source
(ESP32_BOOTLOADER_BUILD_FROM_SOURCE)"
+comment "Flash Encryption support requires building the bootloader from source
(ESP32_BOOTLOADER_BUILD_FROM_SOURCE)"
depends on !ESP32_BOOTLOADER_BUILD_FROM_SOURCE
choice ESP32_SECURE_FLASH_ENCRYPTION_MODE
diff --git a/arch/xtensa/src/esp32s2/Bootloader.mk
b/arch/xtensa/src/esp32s2/Bootloader.mk
index 3ad1fc0..54248df 100644
--- a/arch/xtensa/src/esp32s2/Bootloader.mk
+++ b/arch/xtensa/src/esp32s2/Bootloader.mk
@@ -78,7 +78,14 @@ ifeq ($(CONFIG_ESP32S2_APP_FORMAT_MCUBOOT),y)
$(if $(CONFIG_ESP32S2_SECURE_BOOT_ALLOW_JTAG),$(call
cfg_en,CONFIG_SECURE_BOOT_ALLOW_JTAG)) \
$(if $(CONFIG_ESP32S2_SECURE_BOOT_ALLOW_EFUSE_RD_DIS),$(call
cfg_en,CONFIG_SECURE_BOOT_V2_ALLOW_EFUSE_RD_DIS)) \
$(if $(CONFIG_ESP32S2_SECURE_DISABLE_ROM_DL_MODE),$(call
cfg_en,CONFIG_SECURE_DISABLE_ROM_DL_MODE)) \
+ $(if $(CONFIG_ESP32S2_SECURE_ENABLE_SECURE_ROM_DL_MODE),$(call
cfg_en,CONFIG_SECURE_ENABLE_SECURE_ROM_DL_MODE)) \
$(if $(CONFIG_ESP32S2_SECURE_INSECURE_ALLOW_DL_MODE),$(call
cfg_en,CONFIG_SECURE_INSECURE_ALLOW_DL_MODE)) \
+ $(if $(CONFIG_ESP32S2_SECURE_FLASH_ENC_ENABLED),$(call
cfg_en,CONFIG_SECURE_FLASH_ENC_ENABLED)) \
+ $(if
$(CONFIG_ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT),$(call
cfg_en,CONFIG_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT)) \
+ $(if
$(CONFIG_ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_RELEASE),$(call
cfg_en,CONFIG_SECURE_FLASH_ENCRYPTION_MODE_RELEASE)) \
+ $(if
$(CONFIG_ESP32S2_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC),$(call
cfg_en,CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC)) \
+ $(if
$(CONFIG_ESP32S2_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE),$(call
cfg_en,CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE)) \
+ $(if
$(CONFIG_ESP32S2_SECURE_FLASH_REQUIRE_ALREADY_ENABLED),$(call
cfg_en,CONFIG_SECURE_FLASH_REQUIRE_ALREADY_ENABLED)) \
$(call cfg_val,CONFIG_ESP_BOOTLOADER_SIZE,0xF000) \
$(call
cfg_val,CONFIG_ESP_APPLICATION_PRIMARY_START_ADDRESS,$(CONFIG_ESP32S2_OTA_PRIMARY_SLOT_OFFSET))
\
$(call
cfg_val,CONFIG_ESP_APPLICATION_SIZE,$(CONFIG_ESP32S2_OTA_SLOT_SIZE)) \
diff --git a/arch/xtensa/src/esp32s2/Kconfig b/arch/xtensa/src/esp32s2/Kconfig
index da2c9cb..23152d1 100644
--- a/arch/xtensa/src/esp32s2/Kconfig
+++ b/arch/xtensa/src/esp32s2/Kconfig
@@ -81,6 +81,16 @@ config ESP32S2_FLASH_16M
bool
default n
+config ESP32S2_ESPTOOLPY_NO_STUB
+ bool "Disable download stub"
+ default n
+ ---help---
+ The flasher tool sends a precompiled download stub first by
default.
+ That stub allows things like compressed downloads and more.
+ Usually you should not need to disable that feature.
+ It is only required to be disabled in certain scenarios when
either
+ Secure Boot V2 or Flash Encryption is enabled.
+
config ESP32S2_FLASH_DETECT
bool "Auto-detect FLASH size"
default y
diff --git a/arch/xtensa/src/esp32s2/Kconfig.security
b/arch/xtensa/src/esp32s2/Kconfig.security
index f9b1297..f03c975 100644
--- a/arch/xtensa/src/esp32s2/Kconfig.security
+++ b/arch/xtensa/src/esp32s2/Kconfig.security
@@ -20,7 +20,7 @@ config ESP32S2_SECURE_BOOT
if ESP32S2_SECURE_BOOT
-comment "Secure Boot support requires building bootloader from source
(ESP32S2_BOOTLOADER_BUILD_FROM_SOURCE)"
+comment "Secure Boot support requires building the bootloader from source
(ESP32S2_BOOTLOADER_BUILD_FROM_SOURCE)"
depends on !ESP32S2_BOOTLOADER_BUILD_FROM_SOURCE
config ESP32S2_SECURE_BOOT_BUILD_SIGNED_BINARIES
@@ -100,8 +100,54 @@ config ESP32S2_SECURE_BOOT_INSECURE
endif # ESP32S2_SECURE_BOOT
+comment "Flash Encryption"
+
+config ESP32S2_SECURE_FLASH_ENC_ENABLED
+ bool "Enable Flash Encryption on boot (READ HELP FIRST)"
+ default n
+ depends on ESP32S2_APP_FORMAT_MCUBOOT
+ ---help---
+ If this option is set, flash contents will be encrypted by the
bootloader on first boot.
+
+ Note: After first boot, the system will be permanently
encrypted. Re-flashing an encrypted
+ system is complicated and not always possible.
+
+ Read
https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/security/flash-encryption.html
+ before enabling.
+
+if ESP32S2_SECURE_FLASH_ENC_ENABLED
+
+comment "Flash Encryption support requires building the bootloader from source
(ESP32S2_BOOTLOADER_BUILD_FROM_SOURCE)"
+ depends on !ESP32S2_BOOTLOADER_BUILD_FROM_SOURCE
+
+choice ESP32S2_SECURE_FLASH_ENCRYPTION_MODE
+ bool "Enable usage mode"
+ default ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ ---help---
+ By default, Development mode is enabled which allows ROM
download mode to perform Flash Encryption
+ operations (plaintext is sent to the device, and it encrypts it
internally and writes ciphertext
+ to flash). This mode is not secure, it's possible for an
attacker to write their own chosen plaintext
+ to flash.
+
+ Release mode should always be selected for production or
manufacturing. Once enabled it's no longer
+ possible for the device in ROM Download Mode to use the Flash
Encryption hardware.
+
+ Refer to the Flash Encryption section of the ESP-IDF
Programmer's Guide for details:
+
https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/security/flash-encryption.html#flash-encryption-configuration
+
+ config ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ bool "Development (NOT SECURE)"
+ select ESP32S2_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC
+
+ config ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_RELEASE
+ bool "Release"
+
+endchoice
+
+endif # ESP32S2_SECURE_FLASH_ENC_ENABLED
+
menu "Potentially insecure options"
- visible if ESP32S2_SECURE_BOOT_INSECURE
+ visible if ESP32S2_SECURE_BOOT_INSECURE ||
ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
# NOTE: Options in this menu NEED to have ESP32S2_SECURE_BOOT_INSECURE
# and/or ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT in "depends
on", as the menu
@@ -112,7 +158,7 @@ menu "Potentially insecure options"
config ESP32S2_SECURE_BOOT_ALLOW_JTAG
bool "Allow JTAG Debugging"
default n
- depends on ESP32S2_SECURE_BOOT_INSECURE
+ depends on ESP32S2_SECURE_BOOT_INSECURE ||
ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
---help---
If not set (default), the bootloader will permanently disable
JTAG (across entire chip) on first boot
when either Secure Boot or Flash Encryption is enabled.
@@ -142,12 +188,51 @@ config ESP32S2_SECURE_BOOT_ALLOW_EFUSE_RD_DIS
then it is __NOT__ possible to read/write efuses using
espefuse.py utility.
However, efuse can be read/written from the application.
+config ESP32S2_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC
+ bool "Leave UART bootloader encryption enabled"
+ default n
+ depends on ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ ---help---
+ If not set (default), the bootloader will permanently disable
UART bootloader encryption access on
+ first boot. If set, the UART bootloader will still be able to
access hardware encryption.
+
+ It is recommended to only set this option in testing
environments.
+
+config ESP32S2_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE
+ bool "Leave UART bootloader flash cache enabled"
+ default n
+ depends on ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ ---help---
+ If not set (default), the bootloader will permanently disable
UART bootloader flash cache access on
+ first boot. If set, the UART bootloader will still be able to
access the flash cache.
+
+ Only set this option in testing environments.
+
+config ESP32S2_SECURE_FLASH_REQUIRE_ALREADY_ENABLED
+ bool "Require Flash Encryption to be already enabled"
+ default n
+ depends on ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+ ---help---
+ If not set (default), and Flash Encryption is not yet enabled
in eFuses, the 2nd stage bootloader
+ will enable Flash Encryption: generate the Flash Encryption key
and program eFuses.
+ If this option is set, and Flash Encryption is not yet enabled,
the bootloader will error out and
+ reboot.
+ If Flash Encryption is enabled in eFuses, this option does not
change the bootloader behavior.
+
+ Only use this option in testing environments, to avoid
accidentally enabling Flash Encryption on
+ the wrong device. The device needs to have Flash Encryption
already enabled using espefuse.py.
+
endmenu # Potentially insecure options
+config ESP32S2_SECURE_ROM_DL_MODE_ENABLED
+ bool
+ default y if !ESP32S2_SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT
+
choice ESP32S2_SECURE_UART_ROM_DL_MODE
bool "UART ROM download mode"
+ default ESP32S2_SECURE_ENABLE_SECURE_ROM_DL_MODE if
ESP32S2_SECURE_ROM_DL_MODE_ENABLED
default ESP32S2_SECURE_INSECURE_ALLOW_DL_MODE
- depends on ESP32S2_SECURE_BOOT
+ depends on ESP32S2_SECURE_BOOT || ESP32S2_SECURE_FLASH_ENC_ENABLED
config ESP32S2_SECURE_DISABLE_ROM_DL_MODE
bool "Permanently disabled (recommended)"
@@ -166,6 +251,7 @@ choice ESP32S2_SECURE_UART_ROM_DL_MODE
config ESP32S2_SECURE_ENABLE_SECURE_ROM_DL_MODE
bool "Permanently switch to Secure mode (recommended)"
+ select ESP32S2_ESPTOOLPY_NO_STUB
---help---
If set, during startup the app will burn an eFuse bit
to permanently switch the UART ROM
Download Mode into a separate Secure Download mode.
This option can only work if
diff --git a/tools/esp32s2/Config.mk b/tools/esp32s2/Config.mk
index ec56206..8c24c47 100644
--- a/tools/esp32s2/Config.mk
+++ b/tools/esp32s2/Config.mk
@@ -253,7 +253,7 @@ define FLASH
echo "USAGE: make flash ESPTOOL_PORT=<port> [
ESPTOOL_BAUD=<baud> ] [ ESPTOOL_BINDIR=<dir> ]"; \
exit 1; \
fi
- $(eval ESPTOOL_OPTS := -c esp32s2 -p $(ESPTOOL_PORT) -b $(ESPTOOL_BAUD)
$(ESPTOOL_RESET_OPTS))
+ $(eval ESPTOOL_OPTS := -c esp32s2 -p $(ESPTOOL_PORT) -b $(ESPTOOL_BAUD)
$(ESPTOOL_RESET_OPTS) $(if $(CONFIG_ESP32S2_ESPTOOLPY_NO_STUB),--no-stub))
esptool.py $(ESPTOOL_OPTS) write_flash $(ESPTOOL_WRITEFLASH_OPTS)
$(ESPTOOL_BINS)
$(if $(CONFIG_ESP32S2_SECURE_BOOT),$(call HELP_FLASH_BOOTLOADER))
