ECDSA based Secure Boot V2 is not functional for certain input vectors on
ESP32-C5/C61/H2/P4 and on the preview targets ESP32-H4/H21. RSA based Secure
Boot V2 is the recommended scheme where the SoC supports it. This issue will be
fixed in a future hardware ECO revision; more details will be shared through the
hardware errata document.
A new hidden Kconfig option SECURE_BOOT_V2_ECDSA_INSECURE marks the affected
mass-production SoCs (ESP32-C5/C61/H2/P4). On these SoCs, when hardware Secure
Boot V2 is enabled, the ECDSA (V2) signing scheme is no longer offered by
default; it must be turned on explicitly via SECURE_BOOT_V2_FORCE_ENABLE_ECDSA
under "Allow potentially insecure options" (CONFIG_SECURE_BOOT_INSECURE). App
signing without hardware Secure Boot is not affected. Note that ESP32-C61 has no
RSA based Secure Boot V2, so it has no Secure Boot scheme enabled by default.
The preview targets ESP32-H4 and ESP32-H21 mark ECDSA Secure Boot V2 as not
supported in their SoC capabilities instead of using the option above. As
ESP32-H4 has no other Secure Boot V2 scheme, Secure Boot is disabled entirely on
it; ESP32-H21 retains RSA based Secure Boot V2.
The security documentation keeps the ECDSA Secure Boot V2 content visible and
adds a warning describing the limitation (including that ECDSA Secure Boot V2 on
ESP32-C61 is not recommended for production). CI apps that exercise ECDSA Secure
Boot V2 on the affected SoCs set CONFIG_SECURE_BOOT_V2_FORCE_ENABLE_ECDSA
accordingly.
- Add ECDSA peripheral chapter and instructions to program efuse key block
- Update security guide for ECDSA peripheral mention for device identity
- Link with ESP-TLS guide about using ECDSA peripheral in TLS connection
It appears that target specific or'ing is not supported through the
docs build. Actual text rendering on the docs site was still using
"default" field from the custom macro, rather than using target
specific.
Added an API to verify the bootloader and app image before revoking the key in Secure Boot V2.
This will help in preventing the device to be bricked if the bootloader/application cannot be
verified by any other keys in efuse
externally with help of espefuse tool
flash_encryption_doc: Fix the document to also inform users about what
happens in case of host generated private key in the Flash encryption process
- Technical details covered in section "15.3.2 Anti-DPA Attack Security
Control" chapter of the ESP32-C6 TRM
- Default configuration sets the security level low for the DPA
protection
- This change applies to all the crypto peripherals where the clock
frequency is dynamically adjusted to create randomness in the power
consumption trajectory
- This configuration helps to make the SCA attacks difficult on the
crypto peripherals
Simple flash read command is not supported if Secure DL mode is enabled on the target.
Remove reference of this from the relevant docs part.
Related: https://github.com/espressif/esptool/issues/810
Related: ESPTOOL-567
Closes IDF-6468
Aditya Patwardhan
harshal.patil
renpeiying
Mahavir Jain
walerii
Harshit Malpani
KonstantinKondrashov
Cai Xin Ying
Marius Vikhammer
Wang Zi Yan
Doc-intern2
Laukik Hase
Linda
Sachin Parekh
mofeifei