528 lines
24 KiB
Plaintext
528 lines
24 KiB
Plaintext
menu "Bootloader config"
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choice LOG_BOOTLOADER_LEVEL
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bool "Bootloader log verbosity"
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default LOG_BOOTLOADER_LEVEL_INFO
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help
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Specify how much output to see in bootloader logs.
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config LOG_BOOTLOADER_LEVEL_NONE
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bool "No output"
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config LOG_BOOTLOADER_LEVEL_ERROR
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bool "Error"
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config LOG_BOOTLOADER_LEVEL_WARN
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bool "Warning"
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config LOG_BOOTLOADER_LEVEL_INFO
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bool "Info"
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config LOG_BOOTLOADER_LEVEL_DEBUG
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bool "Debug"
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config LOG_BOOTLOADER_LEVEL_VERBOSE
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bool "Verbose"
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endchoice
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config LOG_BOOTLOADER_LEVEL
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int
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default 0 if LOG_BOOTLOADER_LEVEL_NONE
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default 1 if LOG_BOOTLOADER_LEVEL_ERROR
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default 2 if LOG_BOOTLOADER_LEVEL_WARN
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default 3 if LOG_BOOTLOADER_LEVEL_INFO
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default 4 if LOG_BOOTLOADER_LEVEL_DEBUG
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default 5 if LOG_BOOTLOADER_LEVEL_VERBOSE
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config BOOTLOADER_SPI_WP_PIN
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int "SPI Flash WP Pin when customising pins via eFuse (read help)"
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range 0 33
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default 7
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depends on FLASHMODE_QIO || FLASHMODE_QOUT
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help
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This value is ignored unless flash mode is set to QIO or QOUT *and* the SPI flash pins have been
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overriden by setting the eFuses SPI_PAD_CONFIG_xxx.
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When this is the case, the eFuse config only defines 3 of the 4 Quad I/O data pins. The WP pin (aka ESP32
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pin "SD_DATA_3" or SPI flash pin "IO2") is not specified in eFuse. That pin number is compiled into the
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bootloader instead.
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The default value (GPIO 7) is correct for WP pin on ESP32-D2WD integrated flash.
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choice BOOTLOADER_VDDSDIO_BOOST
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bool "VDDSDIO LDO voltage"
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default BOOTLOADER_VDDSDIO_BOOST_1_9V
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help
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If this option is enabled, and VDDSDIO LDO is set to 1.8V (using eFuse
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or MTDI bootstrapping pin), bootloader will change LDO settings to
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output 1.9V instead. This helps prevent flash chip from browning out
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during flash programming operations.
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This option has no effect if VDDSDIO is set to 3.3V, or if the internal
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VDDSDIO regulator is disabled via eFuse.
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config BOOTLOADER_VDDSDIO_BOOST_1_8V
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bool "1.8V"
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depends on !ESPTOOLPY_FLASHFREQ_80M
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config BOOTLOADER_VDDSDIO_BOOST_1_9V
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bool "1.9V"
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endchoice
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config BOOTLOADER_FACTORY_RESET
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bool "GPIO triggers factory reset"
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default N
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help
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Allows to reset the device to factory settings:
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- clear one or more data partitions;
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- boot from "factory" partition.
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The factory reset will occur if there is a GPIO input pulled low while device starts up.
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See settings below.
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config BOOTLOADER_NUM_PIN_FACTORY_RESET
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int "Number of the GPIO input for factory reset"
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depends on BOOTLOADER_FACTORY_RESET
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range 0 39
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default 4
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help
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The selected GPIO will be configured as an input with internal pull-up enabled.
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To trigger a factory reset, this GPIO must be pulled low on reset.
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Note that GPIO34-39 do not have an internal pullup and an external one must be provided.
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config BOOTLOADER_OTA_DATA_ERASE
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bool "Clear OTA data on factory reset (select factory partition)"
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depends on BOOTLOADER_FACTORY_RESET
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help
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The device will boot from "factory" partition (or OTA slot 0 if no factory partition is present) after a
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factory reset.
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config BOOTLOADER_DATA_FACTORY_RESET
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string "Comma-separated names of partitions to clear on factory reset"
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depends on BOOTLOADER_FACTORY_RESET
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default "nvs"
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help
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Allows customers to select which data partitions will be erased while factory reset.
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Specify the names of partitions as a comma-delimited with optional spaces for readability. (Like this:
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"nvs, phy_init, ...")
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Make sure that the name specified in the partition table and here are the same.
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Partitions of type "app" cannot be specified here.
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config BOOTLOADER_APP_TEST
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bool "GPIO triggers boot from test app partition"
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default N
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help
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Allows to run the test app from "TEST" partition.
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A boot from "test" partition will occur if there is a GPIO input pulled low while device starts up.
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See settings below.
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config BOOTLOADER_NUM_PIN_APP_TEST
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int "Number of the GPIO input to boot TEST partition"
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depends on BOOTLOADER_APP_TEST
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range 0 39
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default 18
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help
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The selected GPIO will be configured as an input with internal pull-up enabled.
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To trigger a test app, this GPIO must be pulled low on reset.
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After the GPIO input is deactivated and the device reboots, the old application will boot.
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(factory or OTA[x]).
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Note that GPIO34-39 do not have an internal pullup and an external one must be provided.
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config BOOTLOADER_HOLD_TIME_GPIO
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int "Hold time of GPIO for reset/test mode (seconds)"
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depends on BOOTLOADER_FACTORY_RESET || BOOTLOADER_APP_TEST
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default 5
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help
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The GPIO must be held low continuously for this period of time after reset
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before a factory reset or test partition boot (as applicable) is performed.
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config BOOTLOADER_WDT_ENABLE
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bool "Use RTC watchdog in start code"
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default y
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help
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Tracks the execution time of startup code.
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If the execution time is exceeded, the RTC_WDT will restart system.
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It is also useful to prevent a lock up in start code caused by an unstable power source.
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NOTE: Tracks the execution time starts from the bootloader code - re-set timeout, while selecting the
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source for slow_clk - and ends calling app_main.
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Re-set timeout is needed due to WDT uses a SLOW_CLK clock source. After changing a frequency slow_clk a
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time of WDT needs to re-set for new frequency.
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slow_clk depends on ESP32_RTC_CLOCK_SOURCE (INTERNAL_RC or EXTERNAL_CRYSTAL).
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config BOOTLOADER_WDT_DISABLE_IN_USER_CODE
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bool "Allows RTC watchdog disable in user code"
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depends on BOOTLOADER_WDT_ENABLE
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default n
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help
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If it is set, the client must itself reset or disable rtc_wdt in their code (app_main()).
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Otherwise rtc_wdt will be disabled before calling app_main function.
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Use function rtc_wdt_feed() for resetting counter of rtc_wdt.
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Use function rtc_wdt_disable() for disabling rtc_wdt.
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config BOOTLOADER_WDT_TIME_MS
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int "Timeout for RTC watchdog (ms)"
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depends on BOOTLOADER_WDT_ENABLE
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default 9000
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range 0 120000
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help
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Verify that this parameter is correct and more then the execution time.
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Pay attention to options such as reset to factory, trigger test partition and encryption on boot
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- these options can increase the execution time.
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Note: RTC_WDT will reset while encryption operations will be performed.
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config APP_ROLLBACK_ENABLE
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bool "Enable app rollback support"
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default n
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help
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After updating the app, the bootloader runs a new app with the "ESP_OTA_IMG_PENDING_VERIFY" state set.
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This state prevents the re-run of this app. After the first boot of the new app in the user code, the
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function should be called to confirm the operability of the app or vice versa about its non-operability.
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If the app is working, then it is marked as valid. Otherwise, it is marked as not valid and rolls back to
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the previous working app. A reboot is performed, and the app is booted before the software update.
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Note: If during the first boot a new app the power goes out or the WDT works, then roll back will happen.
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Rollback is possible only between the apps with the same security versions.
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config APP_ANTI_ROLLBACK
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bool "Enable app anti-rollback support"
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depends on APP_ROLLBACK_ENABLE
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default n
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help
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This option prevents rollback to previous firmware/application image with lower security version.
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config APP_SECURE_VERSION
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int "eFuse secure version of app"
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depends on APP_ANTI_ROLLBACK
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default 0
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help
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The secure version is the sequence number stored in the header of each firmware.
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The security version is set in the bootloader, version is recorded in the eFuse field
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as the number of set ones. The allocated number of bits in the efuse field
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for storing the security version is limited (see APP_SECURE_VERSION_SIZE_EFUSE_FIELD option).
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Bootloader: When bootloader selects an app to boot, an app is selected that has
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a security version greater or equal that recorded in eFuse field.
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The app is booted with a higher (or equal) secure version.
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The security version is worth increasing if in previous versions there is
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a significant vulnerability and their use is not acceptable.
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Your partition table should has a scheme with ota_0 + ota_1 (without factory).
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config APP_SECURE_VERSION_SIZE_EFUSE_FIELD
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int "Size of the efuse secure version field"
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depends on APP_ANTI_ROLLBACK
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range 1 32
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default 32
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help
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The size of the efuse secure version field. Its length is limited to 32 bits.
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This determines how many times the security version can be increased.
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config EFUSE_SECURE_VERSION_EMULATE
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bool "Emulate operations with efuse secure version(only test)"
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default n
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depends on APP_ANTI_ROLLBACK
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help
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This option allow emulate read/write operations with efuse secure version.
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It allow to test anti-rollback implemention without permanent write eFuse bits.
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In partition table should be exist this partition `emul_efuse, data, 5, , 0x2000`.
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endmenu # Bootloader
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menu "Security features"
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visible if !IDF_CMAKE
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# These three are the actual options to check in code,
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# selected by the displayed options
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config SECURE_SIGNED_ON_BOOT
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bool
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default y
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depends on SECURE_BOOT_ENABLED || SECURE_SIGNED_ON_BOOT_NO_SECURE_BOOT
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config SECURE_SIGNED_ON_UPDATE
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bool
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default y
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depends on SECURE_BOOT_ENABLED || SECURE_SIGNED_ON_UPDATE_NO_SECURE_BOOT
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config SECURE_SIGNED_APPS
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bool
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default y
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depends on SECURE_SIGNED_ON_BOOT || SECURE_SIGNED_ON_UPDATE
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config SECURE_SIGNED_APPS_NO_SECURE_BOOT
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bool "Require signed app images"
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default n
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depends on !SECURE_BOOT_ENABLED
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help
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Require apps to be signed to verify their integrity.
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This option uses the same app signature scheme as hardware secure boot, but unlike hardware secure boot it
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does not prevent the bootloader from being physically updated. This means that the device can be secured
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against remote network access, but not physical access. Compared to using hardware Secure Boot this option
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is much simpler to implement.
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config SECURE_SIGNED_ON_BOOT_NO_SECURE_BOOT
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bool "Bootloader verifies app signatures"
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default n
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depends on SECURE_SIGNED_APPS_NO_SECURE_BOOT
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help
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If this option is set, the bootloader will be compiled with code to verify that an app is signed before
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booting it.
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If hardware secure boot is enabled, this option is always enabled and cannot be disabled.
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If hardware secure boot is not enabled, this option doesn't add significant security by itself so most
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users will want to leave it disabled.
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config SECURE_SIGNED_ON_UPDATE_NO_SECURE_BOOT
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bool "Verify app signature on update"
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default y
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depends on SECURE_SIGNED_APPS_NO_SECURE_BOOT
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help
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If this option is set, any OTA updated apps will have the signature verified before being considered valid.
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When enabled, the signature is automatically checked whenever the esp_ota_ops.h APIs are used for OTA
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updates, or esp_image_format.h APIs are used to verify apps.
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If hardware secure boot is enabled, this option is always enabled and cannot be disabled.
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If hardware secure boot is not enabled, this option still adds significant security against network-based
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attackers by preventing spoofing of OTA updates.
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config SECURE_BOOT_ENABLED
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bool "Enable hardware secure boot in bootloader (READ DOCS FIRST)"
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default n
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help
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Build a bootloader which enables secure boot on first boot.
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Once enabled, secure boot will not boot a modified bootloader. The bootloader will only load a partition
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table or boot an app if the data has a verified digital signature. There are implications for reflashing
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updated apps once secure boot is enabled.
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When enabling secure boot, JTAG and ROM BASIC Interpreter are permanently disabled by default.
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Refer to https://docs.espressif.com/projects/esp-idf/en/latest/security/secure-boot.html before enabling.
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choice SECURE_BOOTLOADER_MODE
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bool "Secure bootloader mode"
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depends on SECURE_BOOT_ENABLED
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default SECURE_BOOTLOADER_ONE_TIME_FLASH
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config SECURE_BOOTLOADER_ONE_TIME_FLASH
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bool "One-time flash"
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help
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On first boot, the bootloader will generate a key which is not readable externally or by software. A
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digest is generated from the bootloader image itself. This digest will be verified on each subsequent
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boot.
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Enabling this option means that the bootloader cannot be changed after the first time it is booted.
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config SECURE_BOOTLOADER_REFLASHABLE
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bool "Reflashable"
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help
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Generate a reusable secure bootloader key, derived (via SHA-256) from the secure boot signing key.
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This allows the secure bootloader to be re-flashed by anyone with access to the secure boot signing
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key.
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This option is less secure than one-time flash, because a leak of the digest key from one device
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allows reflashing of any device that uses it.
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endchoice
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config SECURE_BOOT_BUILD_SIGNED_BINARIES
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bool "Sign binaries during build"
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depends on SECURE_SIGNED_APPS
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default y
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help
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Once secure boot or signed app requirement is enabled, app images are required to be signed.
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If enabled (default), these binary files are signed as part of the build process. The file named in
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"Secure boot private signing key" will be used to sign the image.
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If disabled, unsigned app/partition data will be built. They must be signed manually using espsecure.py
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(for example, on a remote signing server.)
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config SECURE_BOOT_SIGNING_KEY
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string "Secure boot private signing key"
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depends on SECURE_BOOT_BUILD_SIGNED_BINARIES
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default secure_boot_signing_key.pem
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help
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Path to the key file used to sign app images.
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Key file is an ECDSA private key (NIST256p curve) in PEM format.
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Path is evaluated relative to the project directory.
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You can generate a new signing key by running the following command:
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espsecure.py generate_signing_key secure_boot_signing_key.pem
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See https://docs.espressif.com/projects/esp-idf/en/latest/security/secure-boot.html for details.
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config SECURE_BOOT_VERIFICATION_KEY
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string "Secure boot public signature verification key"
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depends on SECURE_SIGNED_APPS && !SECURE_BOOT_BUILD_SIGNED_BINARIES
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default signature_verification_key.bin
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help
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Path to a public key file used to verify signed images. This key is compiled into the bootloader and/or
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app, to verify app images.
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Key file is in raw binary format, and can be extracted from a
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PEM formatted private key using the espsecure.py
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extract_public_key command.
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Refer to https://docs.espressif.com/projects/esp-idf/en/latest/security/secure-boot.html before enabling.
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choice SECURE_BOOTLOADER_KEY_ENCODING
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bool "Hardware Key Encoding"
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depends on SECURE_BOOTLOADER_REFLASHABLE
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default SECURE_BOOTLOADER_NO_ENCODING
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help
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In reflashable secure bootloader mode, a hardware key is derived from the signing key (with SHA-256) and
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can be written to eFuse with espefuse.py.
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Normally this is a 256-bit key, but if 3/4 Coding Scheme is used on the device then the eFuse key is
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truncated to 192 bits.
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This configuration item doesn't change any firmware code, it only changes the size of key binary which is
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generated at build time.
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config SECURE_BOOTLOADER_KEY_ENCODING_256BIT
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bool "No encoding (256 bit key)"
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config SECURE_BOOTLOADER_KEY_ENCODING_192BIT
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bool "3/4 encoding (192 bit key)"
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endchoice
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config SECURE_BOOT_INSECURE
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bool "Allow potentially insecure options"
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depends on SECURE_BOOT_ENABLED
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default N
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help
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You can disable some of the default protections offered by secure boot, in order to enable testing or a
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custom combination of security features.
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Only enable these options if you are very sure.
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Refer to https://docs.espressif.com/projects/esp-idf/en/latest/security/secure-boot.html before enabling.
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config FLASH_ENCRYPTION_ENABLED
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bool "Enable flash encryption on boot (READ DOCS FIRST)"
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default N
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help
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If this option is set, flash contents will be encrypted by the bootloader on first boot.
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Note: After first boot, the system will be permanently encrypted. Re-flashing an encrypted
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system is complicated and not always possible.
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Read https://docs.espressif.com/projects/esp-idf/en/latest/security/flash-encryption.html before enabling.
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config FLASH_ENCRYPTION_INSECURE
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bool "Allow potentially insecure options"
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depends on FLASH_ENCRYPTION_ENABLED
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default N
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help
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You can disable some of the default protections offered by flash encryption, in order to enable testing or
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a custom combination of security features.
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Only enable these options if you are very sure.
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Refer to https://docs.espressif.com/projects/esp-idf/en/latest/security/secure-boot.html and
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https://docs.espressif.com/projects/esp-idf/en/latest/security/flash-encryption.html for details.
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menu "Potentially insecure options"
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visible if FLASH_ENCRYPTION_INSECURE || SECURE_BOOT_INSECURE
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# NOTE: Options in this menu NEED to have SECURE_BOOT_INSECURE
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# and/or FLASH_ENCRYPTION_INSECURE in "depends on", as the menu
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# itself doesn't enable/disable its children (if it's not set,
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# it's possible for the insecure menu to be disabled but the insecure option
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# to remain on which is very bad.)
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config SECURE_BOOT_ALLOW_ROM_BASIC
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bool "Leave ROM BASIC Interpreter available on reset"
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depends on SECURE_BOOT_INSECURE || FLASH_ENCRYPTION_INSECURE
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default N
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help
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By default, the BASIC ROM Console starts on reset if no valid bootloader is
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read from the flash.
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When either flash encryption or secure boot are enabled, the default is to
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disable this BASIC fallback mode permanently via eFuse.
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If this option is set, this eFuse is not burned and the BASIC ROM Console may
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remain accessible. Only set this option in testing environments.
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config SECURE_BOOT_ALLOW_JTAG
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bool "Allow JTAG Debugging"
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depends on SECURE_BOOT_INSECURE || FLASH_ENCRYPTION_INSECURE
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default N
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help
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If not set (default), the bootloader will permanently disable JTAG (across entire chip) on first boot
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when either secure boot or flash encryption is enabled.
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Setting this option leaves JTAG on for debugging, which negates all protections of flash encryption
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and some of the protections of secure boot.
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Only set this option in testing environments.
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config SECURE_BOOT_ALLOW_SHORT_APP_PARTITION
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bool "Allow app partition length not 64KB aligned"
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depends on SECURE_BOOT_INSECURE
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help
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If not set (default), app partition size must be a multiple of 64KB. App images are padded to 64KB
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length, and the bootloader checks any trailing bytes after the signature (before the next 64KB
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boundary) have not been written. This is because flash cache maps entire 64KB pages into the address
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|
space. This prevents an attacker from appending unverified data after the app image in the flash,
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|
causing it to be mapped into the address space.
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|
|
Setting this option allows the app partition length to be unaligned, and disables padding of the app
|
|
image to this length. It is generally not recommended to set this option, unless you have a legacy
|
|
partitioning scheme which doesn't support 64KB aligned partition lengths.
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|
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config FLASH_ENCRYPTION_UART_BOOTLOADER_ALLOW_ENCRYPT
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|
bool "Leave UART bootloader encryption enabled"
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|
depends on FLASH_ENCRYPTION_INSECURE
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|
default N
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|
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.
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|
|
|
It is recommended to only set this option in testing environments.
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|
|
|
config FLASH_ENCRYPTION_UART_BOOTLOADER_ALLOW_DECRYPT
|
|
bool "Leave UART bootloader decryption enabled"
|
|
depends on FLASH_ENCRYPTION_INSECURE
|
|
default N
|
|
help
|
|
If not set (default), the bootloader will permanently disable UART bootloader decryption access on
|
|
first boot. If set, the UART bootloader will still be able to access hardware decryption.
|
|
|
|
Only set this option in testing environments. Setting this option allows complete bypass of flash
|
|
encryption.
|
|
|
|
config FLASH_ENCRYPTION_UART_BOOTLOADER_ALLOW_CACHE
|
|
bool "Leave UART bootloader flash cache enabled"
|
|
depends on FLASH_ENCRYPTION_INSECURE
|
|
default N
|
|
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.
|
|
|
|
endmenu # Potentially Insecure
|
|
|
|
config FLASH_ENCRYPTION_DISABLE_PLAINTEXT
|
|
bool "Disable serial reflashing of plaintext firmware"
|
|
depends on FLASH_ENCRYPTION_ENABLED
|
|
default y if SECURE_BOOT_ENABLED
|
|
default n if !SECURE_BOOT_ENABLED
|
|
help
|
|
If this option is enabled, flash encryption is permanently enabled after first boot by write-protecting
|
|
the FLASH_CRYPT_CNT efuse. This is the recommended configuration for a secure production system.
|
|
|
|
If this option is disabled, FLASH_CRYPT_CNT is left writeable and up to 4 plaintext re-flashes are allowed.
|
|
An attacker with physical access will be able to read out encrypted flash contents until all plaintext
|
|
re-flashes have been used up.
|
|
|
|
If this option is disabled and hardware Secure Boot is enabled, Secure Boot must be configured in
|
|
Reflashable mode so that a new Secure Boot digest can be flashed at the same time as plaintext firmware.
|
|
This combination is not secure and should not be used for a production system.
|
|
|
|
endmenu # Security features
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