Commit graph

9 commits

Author SHA1 Message Date
Anurag Kar
ba2ff1876f Enable secure boot only after encrypting flash
This prevents a device from being bricked in case when both secure boot & flash encryption are enabled and encryption gets interrupted during first boot. After interruption, all partitions on the device need to be reflashed (including the bootloader).

List of changes:
* Secure boot key generation and bootloader digest generation logic, implemented inside function esp_secure_boot_permanently_enable(), has been pulled out into new API esp_secure_boot_generate_digest(). The enabling of R/W protection of secure boot key on EFUSE still happens inside esp_secure_boot_permanently_enable()
* Now esp_secure_boot_permanently_enable() is called only after flash encryption process completes
* esp_secure_boot_generate_digest() is called before flash encryption process starts
2019-05-06 11:34:12 +05:30
Angus Gratton
b364f23e17 secure boot: Support secure boot signatures without hardware secure boot
Allows OTA updates to be secured via signature checks, without requiring the overhead or complexity
of a full secure boot implementation.

Uses same signing mechanisms (build system and/or espsecure.py as Secure Boot).

Requires:
* [ ] More testing
* [ ] Documentation
2018-08-29 17:05:29 +08:00
Angus Gratton
17adb40ca8 bootloader: Calculate SHA256 hash of image on every boot
Makes app image booting more reliable (256-bit rather than 8-bit verification.)

Some measurements, time to boot a 655KB app.bin file and run to app_main() execution.

(All for rev 1 silicon, ie no 340ms spurious WDT delay.)

80MHz QIO mode:
before = 300ms
after = 140ms

40MHz DIO mode:
before = 712ms
after = 577ms

40MHz DIO mode, secure boot enabled
before = 1380ms
after = 934ms

(Secure boot involves two ECC signature verifications (partition table, app) that take approx 300ms each with 80MHz CPU.)
2017-07-19 18:31:59 +10:00
Angus Gratton
43b99edf2b bootloader: Calculate SHA-256 of image while loading/verifying 2017-07-19 18:25:17 +10:00
Angus Gratton
9eb135fd73 Flash encryption: Support enabling flash encryption in bootloader, app support
* App access functions are all flash encryption-aware
* Documentation for flash encryption
* Partition read/write is flash aware
* New encrypted write function
2016-12-01 23:49:12 -08:00
Angus Gratton
e459f803da secure boot: Functional partition table & app signature verification 2016-11-14 11:08:42 +11:00
Angus Gratton
fe66dd85f0 secure boot: Enable based on sdkconfig, remove "secure boot flag" from binary image 2016-11-14 11:08:42 +11:00
Angus Gratton
b5de581399 Secure boot: initial image signature support 2016-11-14 11:08:42 +11:00
Angus Gratton
98a0387854 bootloader_support: Move secure boot code to bootloader_support 2016-11-08 11:13:54 +11:00
Renamed from components/bootloader_support/include/esp_secureboot.h (Browse further)