Goal is that multiple faults would be required to bypass a boot-time signature check.
- Also strengthens some address range checks for safe app memory addresses
- Change pre-enable logic to also check the bootloader signature before enabling SBV2 on ESP32
Add some additional checks for invalid sections:
- Sections only partially in DRAM or IRAM are invalid
- If a section is in D/IRAM, allow the possibility only some is in D/IRAM
- Only pass sections that are entirely in the same type of RTC memory region
* Don't bother checking the chip revision if it looks like the partition
doesn't really contain an app
* Don't print the "info" level about the revision & min revision unless
we're in the bootloader (otherwise it gets printed at random times
during the OTA process)
This saves time when waking up from deep sleep, but potentially decreases
the security of the system. If the application able to modify itself
(especially areas that are loaded into RAM) in flash while running
without crashing or is modifies the cached bits of information about
what was last booted from the bootloader, this could cause security
issues if the user does a "deep sleep reset" since the full validation
is skipped.
Signed-off-by: Tim Nordell <tim.nordell@nimbelink.com>
No need to take this step if we are not doing image validation. The
obfuscation only buys us a tiny bit of "security" anyways since the
main parts of flash are memory mapped, too. This saves a little bit of
wake-up time when waking up from deep sleep when the
BOOTLOADER_SKIP_VALIDATE_IN_DEEP_SLEEP option is set.
Signed-off-by: Tim Nordell <tim.nordell@nimbelink.com>
Made MMU pages available check in `esp_image_format.c`
This now makes it possible to map and process bootoader image as well in chunks when image doesn't fit completely into available free pages.
Signed-off-by: Vikram Dattu <vikram.dattu@espressif.com>
1. separate rom include files and linkscript to esp_rom
2. modefiy "include rom/xxx.h" to "include esp32/rom/xxx.h"
3. Forward compatible
4. update mqtt
When CONFIG_ESP32_RTCDATA_IN_FAST_MEM is enabled, RTC data is placed
into RTC_FAST memory region, viewed from the data bus. However the
bootloader was missing a check that this region should not be
overwritten after deep sleep, which caused .rtc.bss segment to loose
its contents after wakeup.
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
Added bootloader_common_get_sha256_of_partition() and esp_partition_get_sha256() - get or calculate SHA-256
digest for app and data partitions.
Added bootloader_sha256_hex_to_str() - helps to print SHA-256 digest
Added esp_partition_check_identity() - compares two partitions by SHA-256 digest
Refactoring a function esp_image_load() in bootloader space to esp_image_verify() and
bootloader_load_image(). Old name function esp_image_load is deprecated
and will remove in V4.0 version.
spi_flash/sim: Fix error test_host. Add stub for bootloader_common_get_sha256_of_partition in sim/stubs
Disables app image integrity checks when running under OpenOCD control.
Allows setting breakpoints in flash before application start (just after reset).
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.)
* App access functions are all flash encryption-aware
* Documentation for flash encryption
* Partition read/write is flash aware
* New encrypted write function
Default esp-idf builds now show -Wextra warnings (except for a few:
signed/unsigned comparison, unused parameters, old-style C declarations.)
CI building of examples runs with that level raised to -Werror, to catch
those changes going into the main repo.
